Ingredients
Equipment
Method
Make the Homemade Lemon Curd
- In a medium saucepan, whisk together the granulated sugar, egg yolks, and cornstarch until smooth.
- Stir in the fresh lemon zest and fresh lemon juice until well combined.
- Cook the mixture over medium heat, stirring constantly with a rubber spatula, until it thickens to the consistency of pudding, about 5-7 minutes. It should coat the back of your spoon.
- Remove the saucepan from the heat and immediately stir in the sliced unsalted butter until fully melted and incorporated.
- Pour the lemon curd into a shallow container or bowl. Press plastic wrap directly onto the surface of the curd to prevent a skin from forming as it cools. Chill in the refrigerator for at least 2 hours, or until firm.
Bake the Lemon Poppy Seed Cake
- Preheat your oven to 350°F (175°C). Lightly grease and flour a 9x13 inch baking pan, then line the bottom with parchment paper.
- In a large bowl, whisk together the all-purpose flour, cake flour, baking powder, baking soda, kosher salt, and poppy seeds. Set aside.
- In a separate small bowl, whisk together the milk and sour cream until smooth. Set aside.
- In a third large bowl, add the granulated sugar and lemon zest. Rub them together with your fingertips for about 1 minute until the sugar is fragrant and moist. This releases the lemon oils for maximum flavor.
- Whisk in the vegetable oil and melted butter into the lemon sugar. Then, add the eggs one at a time, mixing well after each addition. Stir in the fresh lemon juice and vanilla extract.
- Gradually add about one-third of the dry ingredient mixture to the wet ingredients, mixing until just combined. Then, add half of the milk and sour cream mixture, mixing until incorporated. Repeat, alternating between dry and wet, finishing with the remaining dry ingredients. Mix until just combined, being careful not to overmix.
- Pour the batter evenly into your prepared 9x13 inch baking pan.
- Bake for 35-40 minutes, or until the edges are golden brown and a wooden skewer or toothpick inserted into the center comes out clean.
- Allow the cake to cool in the pan on a wire rack for 15 minutes, then carefully invert it onto the rack to cool completely before frosting.
Prepare and Frost the Cake
- In a large bowl using an electric hand or stand mixer fitted with a paddle attachment, beat the softened cream cheese and room temperature unsalted butter on medium speed until smooth and creamy, about 2 minutes. Scrape down the sides of the bowl as needed.
- Gradually add the powdered sugar, one cup at a time, beating on low speed until combined, then increasing to medium-high until light and fluffy. Mix in the vanilla extract.
- Once the lemon poppy seed cake is completely cooled, spread the cream cheese frosting evenly over the top of the cake.
- Retrieve the chilled lemon curd. Dollop spoonfuls of the firm lemon curd randomly over the frosting.
- Using a knife or a skewer, gently swirl the lemon curd into the frosting to create an attractive marbled effect. Avoid over-swirling to keep the distinct layers.
- For a final touch, sprinkle with extra poppy seeds or a little fresh lemon zest if desired.
- Slice and serve your magnificent lemon poppy seed cake immediately.
Nutrition
Notes
If you don't have cake flour, simply substitute it by combining 3/4 cup (94g) all-purpose flour with 1 1/2 tablespoons cornstarch. Using store-bought lemon curd is a fantastic time-saver if you're short on time. For the cake, feel free to use other mild-flavored oils like canola or light olive oil instead of vegetable oil. You can omit the poppy seeds entirely for a delightful plain lemon cake if preferred. Always ensure all your dairy and eggs are at room temperature for the best batter consistency. For accurate flour measurement, always use the spoon and level method to avoid a dense cake. Room temperature ingredients are essential for a smooth, emulsified batter that bakes evenly. Always use fresh citrus for the most authentic and vibrant lemon flavor. Mix your batter gently; over-mixing can develop gluten and lead to a tough, dry cake. Use a light metal baking pan for an even bake, as dark pans can over-brown the edges. Don't overbake; remove the cake as soon as a toothpick comes out clean to prevent dryness. Ensure your lemon curd is thoroughly chilled before swirling to prevent a runny frosting. If your frosting cracks, it could be from over-mixing or the ingredients being too cold; try re-whipping gently until smooth.