This 5 ingredient keto chocolate cake is the pinnacle of sugar free desserts! It is incredibly moist, rich and packed with chocolate flavor. Even better, it has only 2.5 net carbs per slice.
Do you want to see everyone at your table sink into silence, occasionally interrupted by a contented sigh? Serve this low carb chocolate cake and watch the magic happen.
I love all the recipes I post on this site, but this recipe is special. That's because it's more than just a chocolate cake. It's a crazy good, wonderfully rich Keto chocolate cake.
This Keto cake does nothing by halves. It contains as much chocolate as it can possibly handle, a generous amount of grass-fed butter and it is just on the right side of sweet. Basically, it is a Keto dream dessert.
It will satisfy the cravings of any chocolate lover. And it also makes a great gluten-free birthday cake!
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Low carb chocolate cake essentials
There are 2 ingredients that increase carbs and sugar in a traditional cake: the wheat flour and, of course, the sugar.
As grains are a no-no on a Keto diet (as well as on a sugar free / low carb diet), most Keto cake recipes use either almond flour or coconut flour or both.
This cake uses only a very small amount of almond flour, which makes it super fudgy, almost like a brownie.
And of course, I'm using a sugar substitute in place of sugar.
For this cake, I've chosen an erythritol/stevia blend. Erythritol is a polyol and cannot be absorbed by our body. Therefore, it's essentially zero carb and does not raise blood sugars.
You can replace the erythritol in this recipe with xylitol, monk fruit sweetener, allulose or with Splenda. If you're using Splenda, be sure to measure using cups as it's lighter in weight than erythritol. And if you're using xylitol, keep it away from dogs. It's highly toxic to them!
Ingredients
It's hard to believe, but you only need 5 ingredients to make this cake:
- Unsweetened chocolate
- Eggs
- Powdered Sweetener
- Almond Flour
- Butter
...and a pinch of salt.
Important: With such few ingredients, they MUST be the best possible quality, especially the chocolate.
There is a range of artisan chocolate makers which produce unsweetened chocolate. The brand I used, Montezuma's, is available at Sainsbury's, in organic shops or online. In the US you can go for a brand like Ghirardelli.
I don't recommend choosing unsweetened Baker's chocolate for this cake. It has the tendency to seize when you melt it and simply does not taste as creamy and mellow as quality chocolate.
How to make Keto chocolate cake
This section contains step by step instructions and photos that show how to make this recipe. See the recipe card for full information on ingredients and quantities.
1.) Whisk the eggs with a hand mixer in a large mixing bowl until they have doubled in size and are frothy.
2.) Add the powdered erythritol and whisk again until well-combined.
TASTE the cake batter and add more sweetener if necessary. I don't have much of a sweet tooth, so you may prefer it a little sweeter than I do.
3.) Melt butter and chocolate and stir until combined. You can do this in a microwave or on the stove - but slowly and gently. TAKE YOUR TIME!!! If the chocolate gets too hot too quickly, it can seize or separate.
Then add the mix to the bowl and fold it in with a spatula or spoon.
4.) See how it's slowly coming together?
5.) Continue stirring until the mixture is fully combined - gooey, creamy goodness!
6.) Lastly, add the almond flour and stir until it is evenly distributed.
7.) Get yourself a springform pan (I used a 20 cm / 8 inch) and line the bottom with parchment paper. Grease the sides with butter or oil and pour in the batter. Bake at 170 Celsius / 340 Fahrenheit on the middle shelf for 30 minutes.
Let the cake cool completely before cutting.
Expert Tips
This is what you need to know to make the recipe perfectly:
Tip #1: Room temperature eggs. Take them out 30 minutes before starting on the cake. Or, warm them up in a bowl with hot water.
Keeping the eggs at room temperature prevents the mix from splitting and becoming lumpy once you add the warm chocolate and butter.
Tip #2: Sweetener must be powdered. You don't want any crunchy bits in your gooey, moist chocolate cake!
Blend granulated sweetener it in a food processor or with the attachment of a stick blender to turn it into a powder.
Tip #3: Take your time melting the chocolate.
Microwave option: When you melt the butter and chocolate in the microwave, do so in 30 second bursts. Mine was mostly melted after 90 seconds in total.
I then left the bowl on the kitchen counter and stirred it from time to time. This caused the rest of the chocolate to melt slowly.
Water bath option: Place the bowl with your chocolate and butter in a heat proof bowl over a pot with boiling water.
Once the chocolate is half-melted, remove the bowl and let it fully melt by stirring occasionally.
Tip #4: Baking at high altitude. If you are baking at high altitude, increase the oven temperature by 10 Celsius / 25 Fahrenheit.
Recipe Variations
SPICE IT UP: To give your keto cake a festive vibe, you could add 1 teaspoon vanilla extract, 1 teaspoon cinnamon plus some cardamom, nutmeg and a pinch of cloves.
For an extra kick, try adding a pinch of chilli! Or grate the zest of 1 orange into the batter.
MAKE IT NUTTY: Add nuts for a bit or crunch - walnuts or pecans would work well.
FLUFFY TEXTURE: This cake is supposed to be fudgy. For a slightly fluffier texture, you could add 1 teaspoon of baking powder or ½ teaspoon of baking soda.
DAIRY-FREE: Replace the butter with coconut oil.
NUT-FREE: Use ¼ cup coconut flour in place of the almond flour.
Toppings
I'm a bit of a purist, so I simply dusted my cake with 100% unsweetened cocoa powder and served on a pretty cake stand.
You could also dust the low carb cake with powdered sweeter.
If you want to go the whole nine yards, make the cream cheese frosting from my keto cupcakes or make a buttercream frosting.
Or how about a quick chocolate ganache? Melt 1 bar (100g) of chocolate and stirring in 3 tablespoon of double / heavy cream and 4 tablespoon powdered sweetener.
You could serve this cake with a dollop of sugar free whipped cream or a scoop of sugar free ice cream.
Recipe FAQs
No. I don't recommend to replace the chocolate with cocoa powder.
To make a layer cake, either slice the cake in half or split the batter between 2 cake pans. The baking time should be about 25 minutes.
Let the layers cool completely, then add the keto chocolate frosting as described below.
Yes! Here are the steps:
Melt 100g / 3.5 oz unsweetened chocolate and 60g / ¼ cup butter.
Stir in 6 tablespoon heavy cream and â…“ cup / 50g powdered sweetener.
Wait until the mixture has cooled and thickened, then spread over the cake or slice it horizontally and fill in between the layers.
I used a 20 cm / 8 inch springform in this recipe. If you only have a standard size 25 cm / 9 inch springform, your chocolate keto cake will be a little flatter, but it still works fine. You may need to reduce the baking time by 5 minutes. Simply check after 25 minutes if the middle of the cake feels firm to the touch.
Store this keto cake in the fridge for 5-6 days. Be sure to keep it in an airtight container. Let the cake come to room temperature before serving.
Sugar free chocolate cake freezes well. Freeze is pre-sliced for up to 3 months. Simply defrost it in the fridge for 48 hours or on the counter for 24 hours.
More Keto Chocolate Desserts
- Chocolate Avocado Cake
- Sugar Free Low Carb Chocolate Birthday Cake
- Keto Chocolate Donuts
- Healthy Chocolate Orange Cake
- Keto Chocolate Cheesecake
Tried this recipe? Give it a star rating below!
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Recipe
Best Ever Keto Chocolate Cake (Sugar Free)
from Sugar Free LondonerNote: The servings slider only changes the first amount in each line and not any subsequent amounts. Please make your own calculations where necessary.
Ingredients
- 300 g / 10.5 oz unsweetened chocolate ***see notes
- 300 g / 10.5 oz butter unsalted (1 â…“ cup melted)
- 6 eggs
- ½ cup / 50g almond flour or ground almonds
- 1 cup / 150g powdered erythritol
- pinch of salt
Instructions
- Heat the oven to 170 Celsius / 340 Fahrenheit. (If you are baking at high altitude, increase the oven temperature by 10 Celsius / 25 Fahrenheit.)
- Melt the butter and chocolate in the microwave (ca 90 seconds - see notes), then stir and wait until dissolved. Alternatively, gently heat in a water bath (a heat proof bowl placed over a pan of boiling water). Set aside.
- In a large bowl, beat the eggs until foamy, then add the sweetener and mix well.
- Add the melted chocolate and butter along with the almond flour and stir with a spoon or spatula until just combined.
- Line the bottom of a 20 cm / 8 inch springform with parchment paper and grease the sides with butter. Pour in the cake batter and bake for approximately 30 minutes on the middle shelf until the top of the cake is firm to the touch, especially in the middle. Â
- Leave to cool before releasing from the cake tin. Once the the cake is completely cooled, dust with cocoa powder.
Paty
Hi
Thanks for the recipe, Im planing on making this cake tomorrow and I just realized that if I use 100%unsweetned Ghirardelli the net carbs per slice go up to 6 net carbs thats a lot! I already bought the ingredients so now I have to look for a more low carb friendly chocolate. I’m not saying its not a good recipe but maybe if others are in a very low carb diet should look for other chocolate options not Girardhelli. Thank you again for the recipe.
Katrin
Hi Paty, thank you for your comment. I'm wondering how how that's possible if the chocolate is unsweetened? I used the Montezuma nutrition to calculate the recipe - surely the Ghirardelli cannot be much different. Can you send me a pic of the nutrition on the pack via email?
Paty
Hi
Sure I can send a pic give me your email. I found another chocolate that had the nutrition closer to the one you used and the batter was delicious, I used monfruit powdered sugar I haven’t taste the cake cause its cooling down but I loved that was super easy to bake, I had the same issue with butter coming out on top but it was just a little bit and I’m pretty sure its my oven (not a very good one for baking) next time I will bake it a 330 or even 320.
Katrin
it's katrin (at) sugarfreelondoner.com
Linda
Can I substitute cocoa powder for the chocolate bar? Maybe increase the butter to compensate?
Katrin
Hi Linda, that's a good question. My personal feeling is that it would be just too much butter, and it may end up too soft. Cacao butter has a finer taste than butter and it's also firmer at room temperature. You'd have to increase the amount of almond flour to hold it together. Basically, you'd end up with a totally different cake. You're probably better off searching for a recipe that uses cacao powder to start with. The only recipe you could use from my site are these chocolate cupcakes, which can be baked as a cake, or this chocolate mug cake, which readers have doubled and tripled to make a really fudgey cake - take look in the comments there!
Nuclear Nana
I am going to try that next time. I used Baker’s chocolate and texture was great but I will add more sweetener next time. Not sweet enough for us and had to cook over 10 minutes longer in my oven at 340°.
Ash Lee
Is the butter 1 1/3 cups before melted or after melted?
Katrin
I don't think it makes a difference. I weighed my butter on a scale, then measured it in the cups once it was melted. If you're using cups, I'd use soft/room temperature butter so you can scoop it out with your cups
Blayne
Hi we followed the ingredients list exactly however it seemed. A little runny to begin with and after 30 mins it was still liquid. We kept checking every 10 mins and finally gave up after an hour. It just failed to set at all and ended up like chocolate soup instead... an awesome tasting chocolate soup however just hard to put candles in for a birthday cake...
Any tips or tricks or ideas for this type of outcome.
Katrin
Hi Blayne, this puzzles me. The eggs should cook at 170 Celsius/340 Fahrenheit and set the cake. The chocolate is firm at room temperature, and the butter makes it soft and fudgy. My best guess is that your oven was not hot enough? If the eggs can't set your cake would remain liquid. Do you use your oven regularly for baking? I did a google search and egg whites actually begin to thicken at 150 F - much lower than the temperature I recommended..... quick thought - did you maybe bake at 170 Fahrenheit instead of 340 - I always give both temperature as I have readers all over the world? Do let me know. I'm so sorry though that the cake did not work out for your birthday. I do hope we can get to the bottom of it so you can make and enjoy it the way it's supposed to look!
consuelo rodriguez
Hello. I am planning to bake this cake, but I just noticed bought granulated erythritol, not powdered. Can I still bake the cake with granulated erythritol.
Katrin
Hi Consuelo, I'd definitely blitz your granulated erythritol in a food processor (or use the attachment of a stick blender) to powder it. In cakes with a "cakey" texture or in cookies it's fine to use granulated sweetener. This cake is really fudgy, so it's better if the sweetener is as fine as possible. Erythritol has the tendency to re-crystallise a bit when cooled, that's why.
Rebecca
This Recipe is incredible, thank you so much. So easy to follow and Tastes amazing!
Ildie
Hi Katrin,
Can I use Stevia Pues sweetener in this cake please. I need to use a lot less so I don’t know if it’s gonna be too dry From that sweeter I really need maybe a teaspoon to make it really sweet. But I don’t know what the texture gonna be..
What do you think?
Thank you!
Katrin
Is this pure stevia extract? I've never tried that, so I'm not sure, actually. Thinking about the recipe, it is the eggs and also the chocolate that bind the cake. The almond flour gives is a slightly cakey (=more fluffy) texture. From that standpoint it should not affect the recipe. You MAY want to add another few tbsp of almond flour to make up for the missing bulk coming from the erythritol. Let us know how it turns out!
Angella
This is awesome! I added half a cup. Of sour cream and a pinch of baking soda also. I add sour cream to all my baking. I can't help myself lol. It was to die for! My question is, are there any other variations of this recipe other than chocolate? Lemon perhaps? Or white chocolate from a jello sugar free pudding mix.? Thoughts?
Katrin
Must try that sour cream hack lol! A white chocolate version could be good. Otherwise I recommend you try my sugar free lemon mug cake. It is moist and rich, people have doubled the recipe with great results, and you can replace the cream in the recipe with sour cream. I think it could tick all your boxes 🙂
Val Thayer
I have taken my cake out of the oven, I used pyure sweetner and only used 1 cup of it instead of 1 1/3 cup like it said originally, I wish I had read all the suggestions because I would have added that little bit extra almond flour like you suggested. The batter still wasn't too runny so I figured it would work. I added a couple of drops of orange flavoring and a pinch of salt. I batter was so good I was tempted to eat a little extra batter My springdoem pan did leak but I am not too worried about that. I did need to leave the cake in 10 extra minutes as it wasn't completely cooked at 30 minutes. I'm so excited to try this, I'll come back later and give you my opinion on taste
Katrin
Can't wait to hear how it turns out!!!! I recently upgraded my springform - I bought 3 different (smaller) sizes - and since then I've never had a problem with leakage. I think they close less well over the years. It's one of those things we keep over decades and eventually age gets the better of them.
Susan
I adjusted the servings to halve the recipe. Your ingredient calculator only adjusts the first amount. For example: 300 g/10.5 oz. Unsweetened chocolate. Metric will adjust, but not the imperial. Ingredient measurements switch places for almond flour and powdered erythritol, so it's the imperial instead of metric measurements that will adjust. Luckily I noticed prior to purchasing or cooking. It looks really good!
Katrin
Unfortunately this is one of the limitations of this recipe plugin I am using. I'm glad you noticed though. Hope you liked the cake!