Keto Lemon Mug Cake
After the first taste of this Keto Lemon Mug Cake Recipe, it will become your new low-carb diet dessert. This keto mug cake recipe is light and fluffy with a tangy lemon flavor and only 4 net carbs. This perfect single-serving sized dessert is great for all occasions and simple to make.
You already know I have a strong affection for both mug cakes and recipes with lemon! Mug cakes are some of the easiest recipes for a sweet tooth on a keto lifestyle.
All my lemon lovers are going to rejoice when they quickly and easily make a sugar free lemon mug cake and try that first bite. The flavor is tangy, zesty, and refreshing. Using all coconut flour instead of almond flour makes this cake light while being moist. It is the perfect dessert for a keto diet.
Looking for more low carb mug cakes? Try my Keto Chocolate Chip Mug Cake or Almond Flour Mug Cake next.
Ingredients
- Butter – You need soft butter. You can set it on the counter ahead of time, so it softens or toss it in the microwave for 10 seconds or so.
- Lemon Extract – If you don’t have lemon extract you can sub in lemon zest. Lemon juice will not work, you need extract or zest for a vibrant lemon flavor.
- Sour Cream – The low carb mug cake is super moist in part because of the sour cream.
- Egg – Don’t skip the egg; it’s what binds the ingredients together and gives the mug cake the right texture.
- Sweetener – You can either use the Trim Healthy Mama Gentle Sweet or use my all-natural sweetener.
- Coconut Flour – Using coconut flour keeps the mug cake gluten-free and full of flavor too.
- Baking Powder – Make sure you are using good quality and non-expired baking powder. It makes the mug cake have the proper rise and keeps it fluffy.
How To Make a Keto Lemon Mug Cake
First Step: Combine softened butter, lemon extract, sour cream, egg, sweetener, coconut flour, and baking powder in a microwave-safe mug or small bowl. You can mix in the wet ingredients and dry ingredients at the same time.
Second Step: Mix well, then microwave for 1 minute and 30 seconds. Eat right from the mug or bowl or invert onto a plate.
Variations
- Dairy-free – Swap in coconut cream for the sour cream and coconut oil for the butter.
- Toppings – Drizzle a little bit of homemade Keto Lemon Curd on top of the mug cake. It’s tangy and delicious. Or add some Keto Lemon Mousse for an out-of-this-world treat. I love pairing this with fresh berries.
- Vanilla – Just swap in vanilla extract for the lemon for a vanilla sweet treat.
- Cream Cheese Frosting – Make a small amount of cream cheese icing and spread on top and then add some raspberries. This combination is amazing!
Common Questions
Can I Share This Mug Cake?
Sure! You certainly can share this easy keto lemon mug cake if you want to. However, like most mug cake recipes, it’s intended to be an individual serving size.
How Do You Store Leftover Lemon Cake?
If there happens to be leftover mug cake left, you can cover the mug cake or put it in a plastic or glass food storage container with a lid. Refrigerate it for 2-3 days. You can warm it back up in the microwave if you want to eat it warm. Heat it for 10 -20 seconds and enjoy it!
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Keto Lemon Mug Cake
Ingredients
- 1 tbsp butter softened
- 2 tbsp coconut flour
- 1 tbsp sour cream
- 1 egg
- 1.5 tbsp Joy Filled Eats Sweetener (or see alternatives in recipe notes)
- 1/2 tsp lemon extract
- 1/4 tsp baking powder
Instructions
- Mix well in a microwave-safe mug.
- Microwave for about 1.5 minutes until fluffy and moist but not wet.
Notes
Nutrition
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Originally Published September 9, 2020. Revised and Republished October 8, 2025.
Amazing game changer! This is the closest thing I’ve had to real cake since I started keto! Light, fluffy and moist, not at all dense like an almond flour version.
Can you use essential oil for the lemon flavoring?
Yes, if you have one that is labeled ‘food safe’. Just add a drop or two to taste.
I love the individual-sized servings plus the speedy delivery. When the need for a sweet snack hits, this delicious recipe keeps me on the keto pathway. I love the freshness of lemon, and this mug delivers.
I like this recipe however I do not have or use microwave!? Do you have any idea how to cook in oven?
You can bake it. I haven’t tested this in the oven but my guess would be 15-18 minutes at 350. You want the center to feel slightly firm to the touch and not jiggle.
I made one each for hubby and I tonight. My microwave may be higher watts – it was a little dry at a 90 seconds. but tasted great! I will back off in 15 second increments until it’s just right. Even hubs liked it and he’s not keto lol. Thank you so much!!
Is this cake light or is it Dense like when using almond flour? Do you think 1/2 lupin 1/2 coconut flour will make it less dense? I just cant handle almond flour for things like this because of how dense it turns out.
This is a lot lighter than an almond flour cake. I’m not familiar with lupin flour so I’m not sure if that would work, sorry.
Great recipe! Exactly what I was looking for. I appreciate you putting how to save or freeze with these too.
Delicious! I softened 1T of cream cheese added a tad of gentle sweet and a dash of raspberry extract for a topping. So good!
Can I use all purpose flour?
In theory, yes, but you would need more and I’m unsure of the amount. But since it is a single-serve recipe it would be easy to test it. Just try using twice the amount of coconut flour in wheat flour. If it doesn’t work the first time you may need a little more.
Can I sub almond flour for coconut flour in this recipe?
You can use this recipe and add lemon extract or zest joyfilledeats.com/keto-vanilla-mug-cake
Is there a way to make this dairy free?
Yes, sub coconut oil for the butter and coconut cream for the sour cream.
Delicious 😋 thank you for sharing your amazing recipe.. I look forward to trying more of them and following you..
Tammy 🙂
just made this today and had it for my snack it was so yummy
Yum! I ended up using allulose as the sweetener as that’s what I had on hand today. Really love the bright lemon flavor from the lemon extract. 🙂
What a delicious cake. I was able to use a fresh lemon from my tree to make this.
How much fresh lemon juice would you use? Would a little lemon zest be a good idea?
Fresh lemon juice isn’t potent enough. You can sub in lemon zest for lemon extract 1:1.