Keto Lemon Poppy Seed Cake – Bright, Moist, and Low-Carb
This Keto Lemon Poppy Seed Cake brings fresh citrus flavor, a moist crumb, and a gentle crunch from poppy seeds—all without the sugar crash. It’s simple to make, bakes up beautifully, and feels special enough for brunch or a cozy afternoon treat. If you’ve been missing classic lemon loaf on a low-carb diet, this version will hit the spot.
The texture is tender, the glaze is zesty, and every slice tastes like sunshine.
Ingredients
Method
- Prep the pan and oven: Preheat your oven to 350°F (175°C). Line a 9x5-inch loaf pan with parchment paper, leaving overhang for easy lifting. Lightly grease the sides.
- Combine dry ingredients: In a large bowl, whisk 2 cups almond flour, 2 tablespoons coconut flour, 2 teaspoons baking powder, and 1/4 teaspoon salt. Break up any lumps for a smooth batter.
- Mix the wet ingredients: In another bowl, whisk 3/4 cup granulated keto sweetener, 4 large eggs, 1/2 cup melted butter (or 1/2 cup avocado oil), 1/2 cup full-fat Greek yogurt, 2 teaspoons vanilla extract, the finely grated zest of 2 lemons, and 3 tablespoons fresh lemon juice.
- Combine wet and dry: Pour wet mixture into dry and stir until just combined. The batter will be thick but spreadable. Fold in 1.5 tablespoons poppy seeds. If the batter seems too thick, add 1–2 tablespoons almond milk.
- Bake: Transfer the batter to the prepared pan and smooth the top. Bake 40–50 minutes, until the top is golden and a toothpick comes out mostly clean with a few moist crumbs. If browning too fast, tent with foil for the last 10–15 minutes.
- Cool properly: Let the cake cool in the pan for 15 minutes, then lift it out using the parchment and transfer to a wire rack. Cool completely before glazing.
- Make the glaze: In a small bowl, whisk 3/4 cup powdered keto sweetener with 2–3 tablespoons lemon juice. Add 1–2 teaspoons almond milk if needed for a pourable consistency. The glaze should be thick but able to drip.
- Glaze and set: Spoon the glaze over the cooled cake, letting it drip down the sides. Sprinkle a pinch of extra poppy seeds or lemon zest if you like. Let the glaze set for 20–30 minutes before slicing.
- Slice and serve: Use a sharp serrated knife to cut neat slices. Enjoy as is, or serve with a dollop of whipped cream and fresh berries.
Transform Your Body in just 6-Weeks. Get Fit, Save Time, and Eat Smart.
Ready to get real results without long workouts or complicated diets? Our 6-week plan is made for busy people who want quick wins and lasting changes.
Get Your Program TodayWhy This Recipe Works
This cake uses a combo of almond flour and coconut flour for structure and moisture without gluten. The almond flour keeps it rich and tender, while a small amount of coconut flour adds lightness. Greek yogurt (or sour cream) makes the crumb velvety and helps the cake stay fresh for days.
Lemon zest and juice offer bold flavor without extra carbs, and poppy seeds bring that nostalgic bakery feel. A simple sugar-free lemon glaze adds shine and a sweet-tart finish.
Shopping List
- Almond flour (super-fine)
- Coconut flour
- Baking powder
- Salt
- Granulated erythritol or allulose (or a blend you like)
- Eggs (room temperature)
- Unsalted butter (melted and slightly cooled) or avocado oil
- Greek yogurt (full-fat) or sour cream
- Lemon zest (from 2 large lemons)
- Fresh lemon juice
- Vanilla extract
- Poppy seeds
- Powdered sweetener (for the glaze)
- Unsweetened almond milk (for thinning the glaze, optional)
Step-by-Step Instructions
- Prep the pan and oven: Preheat your oven to 350°F (175°C). Line a 9×5-inch loaf pan with parchment paper, leaving overhang for easy lifting.
Lightly grease the sides.
- Combine dry ingredients: In a large bowl, whisk 2 cups almond flour, 2 tablespoons coconut flour, 2 teaspoons baking powder, and 1/4 teaspoon salt. Break up any lumps for a smooth batter.
- Mix the wet ingredients: In another bowl, whisk 3/4 cup granulated keto sweetener, 4 large eggs, 1/2 cup melted butter (or 1/2 cup avocado oil), 1/2 cup full-fat Greek yogurt, 2 teaspoons vanilla extract, the finely grated zest of 2 lemons, and 3 tablespoons fresh lemon juice.
- Combine wet and dry: Pour wet mixture into dry and stir until just combined. The batter will be thick but spreadable.
Fold in 1.5 tablespoons poppy seeds. If the batter seems too thick, add 1–2 tablespoons almond milk.
- Bake: Transfer the batter to the prepared pan and smooth the top. Bake 40–50 minutes, until the top is golden and a toothpick comes out mostly clean with a few moist crumbs.
If browning too fast, tent with foil for the last 10–15 minutes.
- Cool properly: Let the cake cool in the pan for 15 minutes, then lift it out using the parchment and transfer to a wire rack. Cool completely before glazing.
- Make the glaze: In a small bowl, whisk 3/4 cup powdered keto sweetener with 2–3 tablespoons lemon juice. Add 1–2 teaspoons almond milk if needed for a pourable consistency.
The glaze should be thick but able to drip.
- Glaze and set: Spoon the glaze over the cooled cake, letting it drip down the sides. Sprinkle a pinch of extra poppy seeds or lemon zest if you like. Let the glaze set for 20–30 minutes before slicing.
- Slice and serve: Use a sharp serrated knife to cut neat slices.
Enjoy as is, or serve with a dollop of whipped cream and fresh berries.
How to Store
- Room temperature: Store the glazed cake in an airtight container for up to 2 days. Keep away from direct sunlight and heat.
- Refrigerator: For longer freshness, refrigerate up to 5–6 days. Let slices sit at room temp for 10 minutes before serving for best texture.
- Freezer: Freeze individual slices wrapped tightly, then place in a freezer bag for up to 2 months.
Thaw overnight in the fridge or at room temperature for 30–45 minutes.
Why This is Good for You
This cake is low in carbs and free of refined sugar, making it friendly for keto and low-carb lifestyles. Almond flour provides healthy fats and vitamin E, while coconut flour adds fiber without spiking blood sugar. Eggs and Greek yogurt bring protein and a satisfying texture.
Lemon adds brightness and a burst of vitamin C. With thoughtful ingredients, you get a dessert that feels indulgent but supports steady energy.
Common Mistakes to Avoid
- Overbaking: Keto cakes can dry out if left too long in the oven. Start checking at 38 minutes and pull it when the center is set and a tester has a few moist crumbs.
- Skipping room-temperature ingredients: Cold eggs or yogurt can cause the batter to seize or bake unevenly.
Let them sit out for 20–30 minutes first.
- Packing flour: Scooping almond flour tightly can lead to a dense cake. Fluff it with a fork and level with a knife when measuring, or weigh if you can.
- Overmixing: Stir until just combined to keep the crumb tender.
- Too-thin glaze: A watery glaze won’t set. Add more powdered sweetener to thicken, or chill the cake briefly before glazing.
Recipe Variations
- Meyer lemon loaf: Swap regular lemons for Meyer lemons for a sweeter, floral note.
Reduce sweetener slightly if desired.
- Lemon-blueberry: Fold in 3/4 cup fresh blueberries tossed with a teaspoon of almond flour. Add 5–10 minutes to the bake time.
- Lemon almond: Add 1/2 teaspoon almond extract to the batter and top with toasted sliced almonds before baking.
- Lemon orange twist: Use half lemon zest and half orange zest for a citrus blend. Keep the lemon juice the same for tartness.
- Dairy-free: Use avocado oil instead of butter and a thick dairy-free yogurt.
Check sweetness, as some dairy-free yogurts are tangier.
- Mini loaves or muffins: Bake in a muffin tin (12 muffins) for 18–22 minutes, or in mini loaf pans for 25–30 minutes, until tops spring back.
FAQ
Can I use only almond flour and skip the coconut flour?
Yes, but the texture will be slightly denser and more moist. If skipping coconut flour, add about 3 extra tablespoons of almond flour to balance the batter and watch the bake time closely.
What sweetener works best?
Allulose gives a softer crumb and less cooling effect, while erythritol blends hold structure and set the glaze well. A 50/50 blend of erythritol and allulose is a nice middle ground.
How do I keep the cake from crumbling?
Measure flours accurately, don’t overbake, and let the cake cool fully before slicing.
Using Greek yogurt and enough eggs helps bind the crumb and keep it moist.
Can I make it nut-free?
You can try a sunflower seed flour substitute for almond flour, but the flavor and color may change slightly. Keep the coconut flour, as it balances moisture and texture.
Is the glaze necessary?
No, but it adds brightness and a bakery-style finish. If skipping the glaze, increase lemon zest in the batter by 1 teaspoon to boost citrus flavor.
How many net carbs per slice?
Exact numbers vary by brand and serving size, but a typical slice (1/12 of the loaf) is around 3–5g net carbs when using almond flour, coconut flour, and a sugar-free sweetener.
Always calculate with your specific ingredients.
Can I add protein powder?
Yes. Replace 2–3 tablespoons of almond flour with an unflavored or vanilla whey or egg white protein. You may need 1–2 tablespoons extra liquid if the batter thickens too much.
Final Thoughts
This Keto Lemon Poppy Seed Cake delivers classic flavor with smart, low-carb ingredients.
It’s bright, tender, and easy enough for a weekday bake, but pretty enough for guests. Keep a loaf on hand for breakfasts, snacks, or that moment when you want something sweet without breaking your goals. One slice, and you’ll see why it’s a keeper.
Printable Recipe Card
Want just the essential recipe details without scrolling through the article? Get our printable recipe card with just the ingredients and instructions.
