Keto Lemon Cake
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My keto lemon cake recipe is light and fluffy, with a gorgeous citrus flavor, tender crumb, and tangy lemon cream cheese frosting. Naturally gluten-free and 2 grams of net carbs.
Growing up with a lemon tree in my backyard was something I used to take for granted–until I started baking.
Now, my mom would tell you I visit her on the regular JUST to snag some lemons off the tree. She may have a point, but I pay her back with her favorite lemon desserts…like my keto lemon cake.
I drew inspiration from my keto cake recipe, and loosely adapted it to give it a strong lemon flavor. When testing the cake batter, I found that using lemon extract rather than fresh lemon juice produced a more consistent citrus flavor with no bitterness (something fresh lemon juice can have).
It would be sacrilegious not to use lemon juice at all, though, so I add it to the frosting. The lemon juice in the frosting cuts through the richness of the cream cheese, adding a brightness that the extract alone can’t replicate.
Table of Contents
Why I love this recipe
- Made in one bowl. The batter comes together in under 5 minutes, and no mixers are needed.
- 2 grams of carbs per slice. I tested several sweetener combinations and found that allulose gave the cleanest flavor and dissolved like white sugar.
- No one would guess it’s keto. I’ve brought this cake to more friends’ homes than I can remember, and no one has ever suspected it’s keto-friendly.
Key Ingredients
Here’s what goes into this sugar free lemon cake, along with my kitchen notes. Full measurements are in the recipe card below.
- Blanched almond flour. Also known as superfine almond flour. Avoid using almond meal as it’s too coarse and will yield a crumbly cake.
- Baking powder. I use a full teaspoon of baking powder. Too little and the cake won’t rise at all.
- Coconut oil. Measured in its melted state. Use refined coconut oil to avoid any potential coconut flavor. I did test this with butter, and I didn’t love it mixed into the almond flour.
- Eggs. Room temperature eggs are preferred because they don’t firm up the coconut oil in the cake batter.
- Granulated sweetener. When restesting this cake, I found allulose really does bake best. It dissolves like white sugar and never leaves a bitter aftertaste.
- Lemon extract. I tested the extract and pure lemon juice, and I preferred the extract. Lemon juice will dry out the cake since the batter has no added liquid. Feel free to also add 1 teaspoon of vanilla extract to bring out the natural lemon flavor.
- Yellow food coloring. Optional, but it gives the cake a vibrant color. If you omit it, the cake will be a little pale (but still strong in lemon flavor).
For the lemon frosting:
- Cream cheese. Full-fat cream cheese keeps the frosting fluffy and firm.
- Lemon juice. Adds some extra lemon flavor without being overpowering.
- Sugar-free powdered sugar (keto powdered sweetener). The finer texture blends seamlessly into the cream cheese.
How to make a keto lemon cake
Step 1- Prep. Preheat the oven, line a cake pan with parchment paper, and spray it with cooking spray.
Step 2- Mix. Combine the flour and baking powder. In a separate mixing bowl, combine the remaining ingredients. Fold in the dry ingredients and mix to combine.
Step 3- Bake. Pour the cake batter into the lined pan and bake until a toothpick inserted into the center comes out clean. Let it cool on a cooling rack.
Step 4- Frost. Use a hand mixer to beat the frosting ingredients until smooth, then frost over the cooled cake.
Arman’s recipe tips
- Make a double or triple-tiered cake. Just double or triple the ingredients. I make the triple-tiered version for birthdays, and it holds up really well.
- Add more lemon flavor. If you’re a lemon fiend like I am, feel free to add an extra teaspoon of lemon extract or lemon zest. In culinary school, I learned that zest works best in the batter and juice works best in the frosting. The flavors are more pronounced that way.
- Make cupcakes. Pour the batter into a lined cupcake tin and bake the cupcakes for 17-20 minutes. This recipe will yield a dozen cupcakes.
- Add a splash of milk. Depending on the absorbency of your almond flour, you may find the cake batter is quite thick. Add a splash of unsweetened almond milk, 1 tablespoon at a time, and mix until you have a proper cake batter consistency.
- No egg substitutes. Eggs are non-negotiable for this recipe. Flax eggs or chia eggs won’t give the cake structure or rise. If you need something without eggs, try my vegan lemon cake instead.
Storage instructions
To store: As the cake isn’t made with traditional wheat-based flour and has a frosting, it’s best stored in the refrigerator. Keep the cake covered (in a sealed container or on a plate covered with plastic wrap) and refrigerate for up to 7 days.
To freeze: Place cake slices in a freezer-safe container and freeze them for up to 6 months.
Frequently asked questions
Yes, if you’d prefer to make a keto lemon loaf rather than a cake, you can bake it in a greased loaf pan. Increase the bake time by at least 5 minutes since loaf cakes are denser. Alternatively, you can make my keto lemon pound cake.
You can, but fresh lemon juice can occasionally be bitter depending on the lemon. I recommend tasting it first before adding it to the batter. You can use up to 1 1/2 teaspoons of lemon juice instead of lemon extract.
I wouldn’t swap almond flour for coconut flour in this recipe, as the two yield a very different texture once baked. The liquid ingredients would need to be significantly altered to compensate for it.
Yes. To make this cake in advance, simply bake it, then store it (unfrosted) for up to 2 days in advance. I suggest making the frosting fresh and frosting the cake a few hours before serving.
Keto Lemon Cake
Ingredients
- 2 cups blanched almond flour superfine almond flour
- 1 teaspoon baking powder
- 1/2 cup allulose
- 4 large eggs room temperature
- 2 tablespoon coconut oil melted
- 2 teaspoon lemon extract
- 1-2 drops yellow food coloring Optional
For the frosting
- 8 ounces cream cheese softened
- 1 teaspoon lemon juice
- 1/2 cup sugar free powdered sugar
Instructions
- Preheat the oven to 180C/350F. Grease a 9-inch cake pan and line with parchment paper. Set aside.
- In a small bowl, whisk together the almond flour and baking powder and set aside. In a mixing bowl, whisk together the rest of the ingredients until completely combined.
- Gently add in the dry ingredients and mix well. Transfer the batter into the lined cake pan and bake for 35-40 minutes, or until a skewer comes out clean. Let the cake cool completely before frosting.
To make the frosting
- In a mixing bowl, add all the ingredients and beat together until combined. If too thin, add more sugar free powdered sugar.
Notes
Nutrition
More keto cake recipes to try
- Keto carrot cake– Moist, rich, and layered with a creamy frosting.
- Keto chocolate cake– Rich, fudgy, and made in one bowl. My partner requests this when he’s watching his carbs and needs dessert.
- Keto German chocolate cake– I had to test this cake almost 20 times to create that gooey filling between each cake layer.
- Keto strawberry shortcake– Instead of individual shortcakes, I made one single cake.
Hey there, I tried your carrot cake and it was so good and I really don’t like almond flour so I wanna try your lemon cake however I like it real lemony can I put real lemon juice in and if so, how much thanks
Hi Penny! If you don’t want to use almond flour, sunflower seed flour is a great alternative.
For more lemon flavor, you should be able to add about 1 1/2 tablespoons of lemon juice in the cake batter without affecting the rest of the ingredients.
I would love to try this! Can I replace eggs with flax eggs?
That won’t work, Kathy. Real eggs are needed for structure and rise and to balance out the dry ingredients. Flax eggs won’t work. I do have a vegan lemon cake if you want something eggless.
Thank you for a great lemon keto cake. I made it for a friend’s birthday. Everyone loved it.
The first go, I decided to make it with coconut and almond flour, it was just crumbly. I may not have mixed it in slowly enuf and made a double batch of it. I kept the crumbs and have used them. But I decided to following the recipe exactly and it came out like cake batter and the finished cake was scrumptious. Suggestion: say on the picture 3X’s the recipe for the 3 layer cake. Then it is clearly evident that the recipe needs to be doubled or tripled to make the desired cake height.
I bought an organic lemon extract that had oil in it–that seemed strange.
My bad, I didn’t realize the lemon juice said lemon extract. That explains it lol
The cake turned out tasty! I doubled the lemon juice and still could not taste the lemon flavor that well, so I recommend tripling the amount unless you have a sensitive taste. I also added some vanilla to both the cake and frosting. Consistency of cake turned out like a sponge cake, which I like.
The cake turned out tasty! I doubled the lemon juice and still could not taste the lemon flavor that well, so I recommend tripling the amount unless you have a sensitive taste. I also added some vanilla to both the cake and frosting. Consistency of cake turned out like a sponge cake, which I like.
I’m going to make this for dessert for my little family for Christmas. May get a lemon and zest it and ues it for the juice. Wonder if it’d be best to use the zest in the cake or icing?
Hi Renee- so in culinary school, we were taught that zest is best for the cake batter and juice is best for the icings, because both flavors are more pronounced this way. I’d just be a little wary that the lemon flavor will be very obvious if you do both. If everyone loves lemon, then go for it! If not, I’d keep the icing lemon-juice free. 🙂
It was not pretty but it tastes pretty fabulous.
Can you bake it in a sheet pan? It looks really good, but I need it in a sheet pan.
Yes you can (square pan).
Hi
Thank you for your website. It is really lovely and I am excited about trying your Keto recipes.
My only concern are the portion sizes.
It would be nice to know the size of the pan that you are using. Also it would be nice to know how many slices each cake yields. As I am watching my carbs this information is naturally important.
Thanks again.
Hi there- all of this is included in the recipe card 🙂
Delicious Cake,, wanted it more lemon flavored. Could I substitute white flour? I used dairy free cream cheese and icing was great.
Thanks for the recipe.
Thanks for sharing this Barbara! So glad you liked it. Unfortunately, it wouldn’t be a straight swap for white flour in this recipe because it’s designed to support the almond flour for a low carb cake. If you’re looking for a wheat flour based lemon cake you could try my lemon olive oil cake next 🙂 https://thebigmansworld.com/lemon-olive-oil-cake/