Gluten-Free Lemon Poppy Seed Cake Recipe with Zesty Glaze

This Gluten Free Lemon Poppy Seed Cake is a bright, uplifting bake — soft, tender, and bursting with citrus. Poppy seeds add a pleasant crunch and subtle nuttiness, while a sweet-tangy lemon glaze finishes the cake perfectly. It’s ideal with morning coffee, afternoon tea, or shared with friends for a sunny treat.

slices of lemon poppy seed cake topped with a lemon glaze and slices of lemon made with gluten free ingredients

Recipe Ingredient Notes

Gluten Free Flour: I tested this cake using King Arthur Measure for Measure and Bob’s Red Mill 1-to-1. Both produced a tender, moist crumb. The blends used contain xanthan gum, which helps with structure — other 1:1 blends should work similarly, though I haven’t tested every brand.

Sour Cream: Full-fat sour cream adds moisture, richness, and flavor. Greek yogurt is an acceptable substitute if preferred.

Lemons: This recipe uses a good amount of lemon zest, so organic lemons are ideal when available. Rinse all fruit thoroughly before zesting and juicing.

Poppy Seeds: Poppy seeds are usually found in the spice or baking aisle. They provide a delicate crunch and a mild, nutty note that balances the lemon. If you don’t like them, simply omit them for a classic lemon snack cake.

a collage of ingredients in small bowls needed to make gluten free lemon poppy seed snack cake

Lemon Poppy Seed Cake

This easy lemon poppy seed snacking cake requires no stand mixer — a whisk and a bowl are all you need. I recommend baking in an 8×8-inch square pan for the best thickness; a 9×9-inch pan will produce a thinner cake and may need a shorter bake time.

Cakes made with melted butter tend to have a slightly denser, more tender crumb, which suits this snack cake well.

Preheat oven to 350°F (175°C). Line an 8-inch square pan with parchment paper, leaving an overhang to lift the cake out later. Set aside.
In a small bowl, whisk together 210g gluten free multi-purpose flour (containing xanthan gum), 1½ tsp baking powder, ½ tsp baking soda, ½ tsp kosher salt, and 10g poppy seeds. Set aside.
Cut 113g unsalted butter into pieces and melt in the microwave or in a small saucepan over low heat. Let cool slightly while you prepare the lemon sugar.
In a large bowl, combine 145g granulated sugar with the zest of 3 lemons. Rub the zest into the sugar to release the oils and intensify the lemon flavor.
Add the melted butter and 1 tsp vanilla extract to the lemon sugar and whisk until smooth.
Whisk in 2 large eggs, one at a time, ensuring each is fully incorporated before adding the next.
Stir in 230g room-temperature sour cream until smooth and lump-free.
Gradually add the dry ingredients, whisking to combine, then fold gently with a flexible spatula until no streaks of flour remain.
Transfer the batter to the prepared pan and smooth the top. Tap the pan on the counter to release any air bubbles.
Bake 32–35 minutes, or until a toothpick inserted in the center comes out clean and the top is golden. Baking times can vary by oven and pan size.
Cool the cake in the pan on a wire rack for 10 minutes, then lift it out using the parchment overhang and let it cool completely before glazing.

Lemon Glaze

Whisk 130g sifted powdered sugar with 25–35g fresh lemon juice until smooth. Add a little lemon zest for extra brightness. The glaze should be thick but pourable; add more juice to thin it if needed.
Pour the glaze over the fully cooled cake and spread gently with a small offset spatula or the back of a spoon.
Let the glazed cake sit 10–15 minutes to allow the glaze to set before slicing and serving.

Variations of Lemon Poppy Seed Cake

Omit poppy seeds to make a classic lemon snack cake.
Swap the lemon glaze for a small-batch cream cheese frosting and add 1 tbsp lemon juice plus zest for extra tang.
Mix some orange or lime zest with the lemon zest for a different citrus profile (avoid too much orange zest to prevent bitterness).
Gently fold fresh or frozen blueberries into the batter for bursts of fruitiness.

Storage & Freezing

Store leftover cake in an airtight container at room temperature for 3–4 days. If you used cream cheese frosting, refrigerate the cake. For freezing, wrap the completely cooled cake tightly in plastic wrap and then in foil or a freezer-safe bag before glazing. Thaw overnight in the refrigerator or at room temperature, then glaze and serve.

Note about Salt in my Recipes

I typically use Diamond Crystal kosher salt. If you use a different salt (for example Morton’s Kosher), adjust amounts because granule size and salinity vary between brands.

Baking in grams

I recommend baking by weight for best consistency. Digital scales are affordable and precise, especially important for gluten-free baking where ingredient weights differ from conventional flours.

Note about Ovens and Oven Temperatures

Recipes are tested in a conventional oven with the rack in the middle position. If using convection, reduce temperature or monitor baking time closely, as convection ovens can dry baked goods faster.

Substitutions and Modifications

Any ingredient substitutions may change texture and flavor. The recipe here reflects tested proportions and technique.

📖 Recipe

Yield: 8×8 cake (about 16 pieces)