Big flavour, light texture: Try this easy, moist and sugar free lemon mug cake with a deliciously zingy lemon glaze. Low carb, gluten free, keto and suitable for diabetics.
We moved house a couple of months ago, and our new kitchen came with a fitted microwave. We’ve been using it every day. Sod the rays. Microwaves are so practical! We’re living with our mobile phones permanently attached to our ears. We’re breathing in the fumes of London. I drink wine. In the scheme of things, how much more damage are a few microwave rays really going to cause?
Especially when a microwave can produce such a wonderful thing as a sugar free lemon mug cake!
This mug cake, my friends, is a revelation. To think that you can make a perfectly delicious, super easy lemon cake that’s ready in 3 minutes!
By the way, my first attempt at making a cake in the microwave was this divine Low Carb Christmas Pudding.
A sugar free lemon mug cake was a logical follow-up, because one cannot eat Christmas food in, say, July without it feeling a bit odd. Lemon cake, on the other hand, is an all-rounder. A bit like this keto chocolate chip mug cake, which is a must for chocolate lovers, or this divine Keto Peanut Butter Mug Cake.
Let’s get right to it! This is how you make an easy lemon cake recipe in a mug:
1.) Mix your dry ingredients – almond flour, powdered sweetener and baking powder. Powdered sweetener works better than granulated sweetener in this recipe. You can make your own powdered sweetener by blending your granulated sweetener in a food processor or in the attachment of your stick blender.
2.) Add your wet ingredients – lemon juice, cream and an egg and mix with a fork.
3.) If you want to turn your lemon mug cake out onto a plate later, transfer the mixture into a bowl or ramekin which you have greased with melted butter. Or separate the mix into 2 mugs.
4.) This is how your cake looks after it’s been microwaved on high for 90 seconds! It’s moist and spongy – perfect 🙂
5.) Now you turn your lemon cake out onto a plate and top with your lemon drizzle glaze, which you have made with melted butter, cream, a squeeze of lemon juice and powdered sweetener.
6.) Serve and enjoy! Hard to believe this is a sugar free cake, right??? My kids, who are by default brutally honest, absolutely loved it. The cake I shot the recipe video of I shared with a diabetic neighbour who popped by. She also gave it a thumbs up 🙂 I think this is proof enough – lemon mug cake is officially a THING!
Baker’s notes
I think the portion size is quite generous. If you’re not ravenous, you could easily share this mug cake between 4 people, especially if you’re making it with the glaze. I have, however, calculated the nutrition for 2 servings.
You should definitely NOT skip the glaze, because it propels the cake from a delicious dessert into a decadently delicious dessert. If you wanted, you could even poke little holes into your lemon cake after you take it out of the microwave. That way, when you pour over the glaze it sinks into the holes and makes the cake even more moist and yum.
If you’re adventurous, you can even add some poppy seeds or grate some lemon zest into the batter.
I’ve made this cake with both fine almond flour and with ground almonds. If you use almond meal or ground almonds, which are coarser than fine almond flour, add 1-2 additional tablespoons of it so your batter isn’t too liquid.
Made this recipe? Give it a star rating below!
Love lemon? Try these zingy recipes:
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Sugar Free Lemon Mug Cake (Low Carb Recipe)
Ingredients
For the cake
- 4 tbsp almond flour extra fine
- 2 tbsp double/heavy cream
- 1 1/2 tbsp powdered sweetener
- 1 egg
- 2 tbsp lemon juice
- 1/2 tsp baking powder
For the glaze
- 1 tbsp unsalted butter
- 1 tbsp double/heavy cream
- squeeze of lemon juice
- 1 tbsp powdered sweetener
Instructions
- Grease the inside of a ramekin/2 mugs or microwave-safe bowl with melted butter. I used a glass dessert bowl.
- For the cake: Mix all dry ingredients - almond flour, sweetener and baking powder - in a separate bowl.
- Add all wet ingredients and mix thoroughly with a fork. If you find your dough is too liquid add a bit more almond flour.
- Transfer batter into your ramekin/small bowl and level the top.
- Microwave on high for ca 90 seconds. You can also bake the cake at 180 Celsius/360 Fahrenheit for ca 15 minutes.
- Remove from microwave and turn upside down onto a plate.
- For the glaze, melt the butter, then stir in the cream, lemon juice and sweetener.
- Let it cool until the glaze begins to thicken but can still be poured. Then spoon/pour over cake and serve.
Video
Notes
Nutrition
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Linda Olson says
Do you think I can substitute coconut flour?
Katrin Nürnberger says
Yes, but I’d probably only use 1 1/2 tbsp because coconut flour absorbs more liquid. Wait for a couple of minutes and see if you have a good dough consistency!
Tracy N Regard says
I used liquid stevia and I think i used too much. I did one tablespoon liquid sweetener and it was too “stevia” will cut in half next time
Katrin says
Hi Tracy, my feeling is that 8 – 10 drops of stevia glycerite will probably provide enough sweetness. My stevia drops are 4 drops = equivalent to 1 tsp sugar. Let me know how much you ended up using, I’d be super interested to hear.
Nadi says
I really love your recipes but this one tasted a bit eggy which doesn’t really go with sweet 😉 I guess it would be better leaving it to cool
Katrin says
Hi there, you can’t really use less than 1 egg in a mug cake 😉 I’d love to hear if you thought the taste improved when it was cold!
Ron Bryant says
This recipe looks amazing. I will attempt it later today. I thought I knew all abbreviations but I was wrong. I am not familiar with the term ‘ca 30 seconds’ or ‘ca 15 minutes’. Can you enlighten me? Thanks in advance. Cheers!!
Katrin says
Hi there, ‘ca’ is just an abbreviation for “circa”
Christina says
I’m new to low carb/Keto. This was the first thing I attempted to make using almond flour. The cake was a little gritty with more of a biscuit taste. Is this to be expected or do I just need more practice? It wasn’t bad at all just not what I was expecting.
Katrin says
If you used coarse almond flour or ground almonds you would definitely get a more rustic, moist texture to a cake made with wheat flour. Almonds do contain a lot more fat than wheat. If you get yourself superfine Almond flour the finish is more similar to that of regular cakes.
Melanie Caruso says
I’m going to try making this lemon cake with a handful of Blueberries. Hope it works, will be my 1st try at Keto Mug Cake of any kind so don’t know if I should be experimenting yet but what the heck. Love that it looks so simply. Holding my breath…. lol
Katrin says
How did it go? I bet some blueberries in the cake tasted great!
nance says
no microwave how long in a regular oven
Katrin says
I think about 15 minutes at 180 Celsius should do the trick. Check with a skewer if it’s done and add another couple of mins if necessary
Myra Billson says
Hi Katrin, Loved your lemon cake with lemon glaze – like some of your followers my mixture too wet due to using ground almonds – not as absorbent as super-fine almond flour. Simply added coconut flour (Super absorbent!) – worked a treat and gave it a nice coconut flavour. Go Girl! Myra.
Katrin says
Great news! Glad you enjoyed the cake 🙂
Jill Holman says
I had such a craving for something sweet yesterday that I made this lemon mug cake. The only thing I added was some lemon zest. Although this wasn’t really sweet, it satisfied my craving and was absolutely delicious. I’m looking forward to the other half tonight. Such an easy recipe. Thank you.
Katrin says
Good to hear it hit the spot!
Suzanne Lanoue says
Thanks for the recipe! I loved the cake. I didn’t have cream, so I used the 2% milk I had, and it still turned out fine. Just a little crumbly. Instead of the glaze, I just put whipped cream on it.
I put it in a big mug and used Splenda instead of erythritol. I was very generous with both the lemon juice and the Splenda. It was delicious! I shared it on my social media, too, and in a Celiac Facebook group that I frequent. Oh, I gave some to my dog and she loved it, too! Since I used Splenda, it was safe for her (the other type is not safe for dogs).
Katrin says
So glad you enjoyed the cake, and thank you for sharing it on your social media!
Cindy Burton says
I just tried this mug cake and made it exactly as you stated, with one exception. Instead of putting it in two ramekins, I put the whole batter in a small serving bowl (one that typically holds about two cans of corn). After 90 seconds, I got it out and put it on a plate. It did not fall apart at all but was still pretty moist, so I just stuck the plate in the microwave for another 30 seconds and it came out perfect!
I lucked out this week and was able to find a big gallon of frozen raspberries for sale at our local Amish store for $8, so I put about 10 little berries in the same bowl I had just emptied the glaze from and microwaved them for 30 seconds. Then I added a tsp of powdered erythritol to the bowl and whisked them up. Poured them over the glaze and OMG, was it ever delicious!!! However, I must add, I did have one spot on my cake that the raspberries had not run into yet and I grabbed a quick bite of it just to see how well I liked the cake without my fruit topping, and it was delicious too! So, even if you don’t have raspberries, you still need to try this cake!
Katrin says
The addition of the raspberries is making my mouth water!!! Great idea 🙂
Sanny Ang says
Hiyo Katrin
I just made your Lemon Mug Cake…with a few adjustments:
6 Tbsps of almond meal, 2 Tbsps of Coconut Cream & zest & juice of 1 lemon…Microwave High for 120 minutes.
It just pulls away from the mug…Fantastic with a dollop of lemon curd.
Thank you for a wonderful quick dessert.
Katrin says
Sounds yum! Thanks for sharing 🙂
Sharon says
Oh my! So tasty! I ended up using 5 Tbsp of almond flour. Served with fresh sliced strawberries. Delish! Thanks for sharing
Violeta says
Perfect!
Eleanor says
Oh my gosh, YUM!!! I MADe with coconut milk in stead of heavy cream. It was so good. Thank you yet again for another delicious recipe.
Eleanor says
YUM!!! SO good. I made with coconut cream instead of heavy cream, turned out just as good. Thank you for yet another great recipe!!
Katrin says
Good to know you can use coconut cream!
Joy Robinson says
Followed the recipe to a “T” and it was very runny… Didn’t bake up at all. Checked and triple checked the measurements. Should it be more than 4 TB of almond flour? I am a lemonaholic and am beginning to experience withdrawals. ;). Help
Katrin says
Hi Joy, I have made the cake with both super fine almond flour and with ground almonds (=much coarser). If your almond flour is NOT super fine or you’re using ground almonds/ almond meal, you have to use an extra 1-2 tbsp of “flour”, it’s all in the recipe notes at the bottom. I’m sorry you seem to have missed it. Next time, just add more almonds util you have reached the same batter consistency as shown in the video – soft, but not runny.
Tammy says
My cake turned out bitter. I used So Noirished Monk Fruit Erythritol Blend in the measurement you gave. I used the same sweetner in the glaze and it tastes good. I’m not sure where I went wrong.
Katrin says
Hi Tammy, the only ingredient that could taste bitter would be the lemon zest, if you grate in too much of the white peel. Or if you use waxed lemons, which means you might be able to taste the wax and chemicals. Or your almond flour was old and has gone off. You should always store it at room temperature if you’re not using it often. Do you think it could have been any of these?
Susan says
WOW!! Thank you so much for this delicious recipe, Katrin! It is truly the best mug cake that I’ve ever made – so good!! The texture was light and fluffy and the lemon flavour was just perfect.
I added the zest of one lemon, and replaced the cream with coconut milk. I also skipped the glaze, but I didn’t miss it at all. I plan to try making it with tigernut flour, in place of the almond, next time around.
Thanks again!!
Karyn says
I love your easy to follow instructions and this lemon pudding was so quick and easy to make and best of all – it was delicious!
Katrin says
That’s so good to hear Karyn! Thank you for your kind words.
Gayle says
Tried the recipe 2 times and both times failed. Followed recipe to a T. 90 seconds wasn’t long enough so 2nd time it only was done around the edges. Please advise, we love lemon deserts.
Gayle
Katrin says
Hi Gayle, I’m so sorry to hear this! If you measured all ingredients, then I can only think your microwave must be less powerful and you may need to increase the time you cook it.
jeannie says
Hi Katrin, just made this before going to bed LOL it’s very yummy . Did you post macros anywhere?.
Katrin says
Yes, the nutrition info is in the recipe card 🙂
Linda says
Just made and ate, wonderful taste and texture. Used bottled lemon juice and confectioner sugar to sweeten. Great recipe to play with and no huge processed leftovers to gorge on.
Ranjit says
Hi!I’ve tried your recipe and it’s great!do you think I could add cream cheese here or sub the hc?will it ruin the cake?thanks a lot!love your recipes
Katrin says
Yes, I think cream cheese could work in place of the heavy cream – I haven’t tried it, but they have a similar consistency.
Louise Allison says
Not usually a mug cake fan – they leave me a bit ‘meh’ – but fancied something lemony! Just made this, & as I fancied a big lemon hit, I doubled the lemon in the cake & sauce (will add zest next time, but my lemons were a bit aged!!) ….. so then I needed to add more almond flour to get it less runny…… cooked for about 3.5 mins in micro (coz it was maahhooosive!!) Turned it out into a bowl, stabbed it, & drizzled the sauce over…… lush!! It will make 12 servings for me, as it’s super filling….. but just served it with sour cream and a handful of blueberries & can honestly say it’s one of the tastiest sweet things I’ve eaten on keto…. So thank you very much!
Katrin says
Thanks for sharing your microwave timings for doubling the recipe!! And I love it that you loved it!!
Naomi says
This is delicious, Thank you! Mine was wet also, I nearly used less liquid but made it per recipe, except I added shredded lemon zest and used 1 TBSP of swerve. very tangy, delicious, just about perfect, even very moist.
Katrin says
Great news! Glad it worked out 🙂