Keto Lemon Cake – Bright, Zesty, and Low-Carb
A good lemon cake should be light, tender, and full of fresh citrus flavor. This keto version delivers all that with a fraction of the carbs. It’s the kind of cake that works for brunch, birthdays, or a sunny afternoon coffee break.
You get a bright lemon punch, a moist crumb, and a simple glaze that sets just right. Best of all, it’s easy enough for a weeknight but special enough to share.
Overeating is a pattern. This helps you fix that problem. A quick reset for cravings, snacking, and “I’ll start tomorrow” moments.
Built for busy home cooks who want real-life structure. Simple steps that fit meal prep, family dinners, and late-night snack attacks.
What Makes This Recipe So Good
- Real lemon flavor: Fresh lemon zest and juice give the cake honest, vibrant citrus notes. No artificial taste.
- Moist, tender crumb: Almond flour and sour cream keep the texture soft and satisfying, not dry or crumbly.
- Low-carb and gluten-free: Made with almond flour and a keto-friendly sweetener, this cake fits your macros without feeling like a compromise.
- Simple glaze: A tangy lemon glaze ties everything together and adds a pretty finish.
- Foolproof method: Clear steps and pantry-friendly ingredients make this ideal for both new and experienced bakers.
What You’ll Need
- Almond flour: Finely ground, blanched almond flour gives the best texture.
- Coconut flour: Just a little to add structure and reduce density.
- Keto sweetener: Granulated erythritol or an erythritol/monk fruit blend for the batter, powdered version for the glaze.
- Baking powder: For lift.
Make sure it’s fresh.
- Salt: A pinch enhances the lemon and balances sweetness.
- Eggs: Room temperature for better mixing and rise.
- Butter: Melted and slightly cooled. Ghee works too.
- Sour cream: Adds moisture and tenderness. Greek yogurt works as a substitute.
- Almond milk: Or any unsweetened low-carb milk alternative.
- Fresh lemons: You’ll use both zest and juice.
- Vanilla extract: Rounds out the flavor.
- Optional: Lemon extract for extra citrus punch, poppy seeds for texture, and a pinch of turmeric for a sunny hue.
Instructions
- Prep the pan and oven: Heat oven to 350°F (175°C).
Grease an 8-inch round cake pan or loaf pan and line the bottom with parchment.
- Mix dry ingredients: In a large bowl, whisk 2 cups almond flour, 2 tablespoons coconut flour, 1 cup granulated keto sweetener, 2 teaspoons baking powder, and 1/4 teaspoon salt until well combined.
- Whisk wet ingredients: In another bowl, whisk 4 large eggs, 6 tablespoons melted butter, 1/2 cup sour cream, 1/4 cup unsweetened almond milk, 2 teaspoons vanilla extract, the zest of 2 lemons, and 3 tablespoons fresh lemon juice. Add 1/4 teaspoon lemon extract if you want a stronger lemon flavor.
- Combine: Pour wet ingredients into dry. Stir just until smooth.
The batter should be thick but spreadable. If it feels too stiff, add 1–2 tablespoons more almond milk.
- Bake: Spread the batter evenly in the pan. Bake 28–35 minutes, until the top is set, lightly golden, and a toothpick comes out mostly clean with a few moist crumbs.
- Cool: Let the cake cool in the pan 10–15 minutes, then run a knife around the edges and turn onto a rack to cool completely.
- Make the glaze: Whisk 3/4 cup powdered keto sweetener with 1–2 tablespoons fresh lemon juice and 1–2 teaspoons almond milk until smooth and pourable.
It should ribbon off the whisk. Adjust with more liquid or sweetener as needed.
- Glaze and set: Pour the glaze over the cooled cake. Let it set for 15–20 minutes before slicing.
Optional: sprinkle with extra zest or a few poppy seeds.
Keeping It Fresh
- Room temperature: Keep glazed cake covered at room temp for up to 24 hours if your kitchen is cool.
- Refrigerator: Store slices in an airtight container for 4–5 days. The flavor often improves by day two.
- Freezer: Freeze ungazed slices wrapped tightly for up to 2 months. Thaw in the fridge overnight, then glaze before serving.
- Moisture tip: Place a small piece of parchment between slices to prevent sticking and soggy edges.
Health Benefits
- Low net carbs: Sugar-free sweetener and almond flour help keep blood sugar more stable than traditional cake.
- Healthy fats: Almond flour and butter offer satiating fats that support keto macros and help curb cravings.
- Citrus perks: Lemon zest and juice add vitamin C and phytonutrients, along with a bright flavor that can reduce the need for more sweetener.
- Gluten-free: Ideal for those avoiding gluten without sacrificing texture or taste.
What Not to Do
- Don’t overbake: Almond flour dries quickly.
Pull the cake when the center is just set.
- Don’t skip the zest: Most of the lemon flavor lives in the zest. Juice alone isn’t enough.
- Don’t use regular powdered sugar: It kicks you out of ketosis. Stick to powdered keto sweetener for the glaze.
- Don’t overmix: Stir until combined.
Overmixing can make the cake dense.
- Don’t glaze a warm cake: The glaze will run off and soak in, making the top sticky and uneven.
Alternatives
- Dairy-free: Swap butter for coconut oil and sour cream for full-fat coconut yogurt. Use unsweetened coconut milk.
- Lemon-blueberry: Fold 1/2–3/4 cup fresh blueberries into the batter. Toss them in a teaspoon of almond flour first.
- Lemon poppy seed: Add 1–2 tablespoons poppy seeds for classic texture.
- Lemon loaf: Bake in a loaf pan for 45–55 minutes.
Tent with foil if browning too fast.
- Frosting instead of glaze: Beat softened cream cheese, butter, powdered keto sweetener, lemon zest, and a splash of lemon juice until fluffy.
FAQ
Can I use only almond flour and skip coconut flour?
Yes, but the texture will be softer and denser. If skipping coconut flour, add an extra 2–3 tablespoons almond flour and watch the bake time closely.
What sweetener works best?
A granulated erythritol or erythritol/monk fruit blend gives good structure with a clean taste. Use a powdered version for the glaze to avoid grittiness.
How do I get stronger lemon flavor?
Use both zest and juice, and add 1/4–1/2 teaspoon lemon extract.
You can also rub the zest into the sweetener with your fingers to release more oils.
Why did my cake sink in the middle?
Common reasons include underbaking, old baking powder, or too much liquid. Make sure eggs are room temp and the center is fully set before removing from the oven.
Can I make cupcakes instead?
Absolutely. Divide batter into 10–12 lined muffin cups and bake 18–22 minutes.
Glaze or frost once cooled.
Is Greek yogurt okay instead of sour cream?
Yes. Use full-fat Greek yogurt for the closest texture and richness.
How many carbs per slice?
It varies by brand, but a typical slice (1/10 of the cake) is around 4–6g net carbs when using the ingredients listed. Check your labels for exact numbers.
Final Thoughts
This Keto Lemon Cake brings the sunshine without the sugar.
It’s bright, tender, and easy to make, with simple ingredients you can find anywhere. Whether you serve it plain with coffee or dress it up with a glossy lemon glaze, it tastes like a bakery treat that just happens to be low-carb. Keep this recipe in your back pocket for any time you want a fresh, feel-good dessert that fits your goals.
Enjoy a slice today, and maybe another tomorrow—no guilt required.
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