This sugar free mug brownie recipe is super fudgy and chocolatey, keto friendly and gluten free. And best of all, it's cooks in the microwave in just 60 seconds.
Table of contents
Aren't mug cakes just the most brilliant invention ever? I think the ability to produce a healthy single serve cake in 3 minutes from start to finish is nothing short of a miracle.
I have a whole bunch of low carb keto mug cake recipes on my website already. But I have to say, this one is special.
I've made a peanut butter brownie in a mug, and it is egg free! This means it's supremely fudgy, and totally delicious. It makes 1 single serving at just 5.6g net carbs.
Let's take a look at the ingredients:
Ingredients
Peanut Butter - Make sure it's runny and smooth. This is absolutely essential! Hard peanut butter will result in a dry brownie. I like to use brands that are 100% peanuts. You can also use almond butter or any other nut or seed butter.
Coconut Flour - Can be replaced with 3x the amount or almond flour.
Cocoa Powder - This should be 100% unsweetened cocoa.
Powdered Sweetener - I used a powdered erythritol monk fruit sweetener blend. Pure erythritol, allulose, Splenda or Bocha Sweet also work.
Milk - Any nut or seed milk of your choice. I used almond milk.
Baking Powder - To give the brownie a nice lift.
Optional: Pinch of Salt - Either stir it into the brownie batter or sprinkle a few flakes over the top.
Optional: Sugar Free Chocolate Chips - Lily's is a popular brand in the US. Or simply chop up a square of 90% dark chocolate such as Lindt.
How to make a sugar free mug brownie
- Get a mug.
The "mug" can be a proper mug or any microwavable bowl such as a ramekin. My ramekin had a diameter of 3 inches. Option to lightly grease it to prevent sticking.
2. Mix the batter.
I a small bowl, stir together the coconut flour, cocoa powder, baking powder and sweetener with a fork. Break up any clumps.
In another small bowl, combine the nut milk and the peanut butter.
Then, add the dry ingredients to the wet and stir until a brownie batter forms.
Last, fold in the chocolate chips and fill the batter into the prepared mug or ramekin.
3. Microwave.
Microwave the sugar free mug brownie until it's done. That's it!
Microwave timings
Microwave timings will vary according to the wattage of your microwave. Mine operates at 900 Watt.
Below are suggested timings for different power strengths:
- 600W = low power. 80 seconds
- 800W = 70 seconds
- 900W = 60 seconds.
- 1000W = 50 seconds
- 1200W = 40 seconds
I first tested the sugar free brownie after 45 seconds. For all of you who like their brownies super fudgy, this may already be enough.
Also, keep in mind that mug cakes continue to cook in the hot cup after microwaving. So, don't be tempted to overcook!
Oven instructions
To make this single serve brownie recipe in the oven, bake at 180C (160C fan) / 350F for around 7 minutes.
Variations
Caramel swirl brownie: Stir in a swirl of sugar free caramel sauce.
Raspberry brownie: Press a few fresh raspberries into the batter.
Almond flour brownie: Use 2 tablespoons of almond flour instead of the coconut flour.
Add an egg: This makes the brownie fluffier, with a cake-like texture.
As mentioned above, any seed or nut butter can be used in place of peanut butter.
And last but not least, this keto brownie tastes incredible with a scoop of sugar free ice cream!
More keto mug cake recipes
Vanilla Mug Cake Mug Cheesecake 
Peanut Butter Mug Cake
Low Carb Peanut Butter Mug Cake
Keto Triple Chocolate Mug Cake
Low Carb Chocolate Pumpkin Mug Cake
Cinnamon Swirl Coconut Flour Mug Cake
Tried this recipe? Give it a star rating below!
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Sugar Free Mug Brownie
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. ***As an Amazon Associate I earn from qualifying purchases.
Equipment
- microwavable mug or ramekin
Ingredients
- ½ tbsp coconut flour
- 1 tbsp cocoa powder unsweetened
- 1 tbsp powdered sweetener
- ⅛ tsp baking powder
- 1.5 tbsp peanut butter must be smooth and runny
- 3 tbsp almond milk or any nut or seed milk
- 1 tbsp sugar free chocolate chips optional
- pinch of sea salt optional
Instructions
- Lightly grease a microwavable mug or ramekin (3 inch diameter).
- I a small bowl, stir together the coconut flour, cocoa powder, baking powder, sweetener and optional pinch of salt with a fork. Break up any clumps.
- In another small bowl, combine the nut milk and the peanut butter. Then, add the dry ingredients to the wet and stir until a brownie batter forms.
- Last, fold in the chocolate chips and fill the batter into the prepared mug or ramekin. Microwave on high for 60 seconds (900W). See suggested microwave timings in the notes below.
Notes
- 600W = low power. 80 seconds
- 800W = 70 seconds
- 900W = 60 seconds.
- 1000W = 50 seconds
- 1200W = 40 seconds
Nutrition
Red says
I tried this one again just now and put a little extra sugar free sugar in it as I'm a sweet tooth, and microwaved it for just 40 seconds because the first time I tried it at 60 seconds it was way too hard, but this time, the sweetness was perfect, gooey and fudgey aswell, I'll definitely be making this again!. What a difference 20 seconds can make!
TheThalthali says
Just saying thanks for the information, it is really useful. Be safe and happy.
Hin says
Made this today and it was lovely. However do you have this reciepe in grams? How much is 1/8 of baking powder? My one didnt rise as much.
Katrin Nürnberger says
I used measuring spoons. If you like baking, it's a good idea to get some. Otherwise, simply use a teaspoon and ballpark it. This brownie is not supposed to rise much, as you can see from my images, since it does not contain any egg.
Jim Craig says
Hi Katrin, this looks amazing and simple at the same time. Can I swap the coconut flour for almond flour and the peanut butter for almond butter, please?
I've recently bought your 5 book bundle and thought I'd ease myself in gently. My daughters love brownies!
Thanks in advance and have a lovely evening, all the best - Jim
Katrin Nürnberger says
Yes to both. Use around 3x more almond flour than coconut flour. And thank you for your support! Enjoy the cookbooks.
Jim Craig says
Merci madam !
Louise says
More of a gooey fudgy pudding than a brownie (you definitely need a spoon).
I wasn't convinced when I got it out of the microwave
But 5 mins later & a big mug of coffee to wash it down, I'm converted . It's a delicious chocolate, sorry CHOCOLATE, fix. I only ate half as it was quite rich for me. It would be good with cream or ice-cream.
Looking forward to trying the lemon mug cake next xx
nina says
kan dit ook in de airfryer of oven ipv de microgolfoven 🙂 en op hoeveel graden en hoelang dan 🙂
Katrin Nürnberger says
I would go for 180 celsius and about 6-7 minutes.
Bill says
How do ou work out "net Carbs"?
These will surely vary according to wight metabolic rate, muscle mass etc of the person comsumong them - or am I missing something?
Katrin Nürnberger says
Total carbs minus the fibre = net carbs. 🙂