Preheat your oven to 350°F (180°C). This step is crucial for even baking. While the oven heats up, prepare your baking pans. Spray 3 (8-inch) round cake pans with baking spray that contains flour, ensuring the cakes come out easily after baking. Line the bottoms with parchment paper for extra protection.
In the bowl of a stand mixer fitted with the paddle attachment, combine the flour, sugar, poppy seeds, lemon zest, baking powder, salt, and baking soda. Whisk these dry ingredients together by hand to ensure they are evenly distributed. This helps prevent any clumps in your batter.
Add the butter to the mixer bowl. Beat at medium-low speed until the butter is fully incorporated and the mixture resembles coarse crumbs, about 2 minutes. You want to ensure there are no large chunks of butter remaining.
In a separate medium bowl, whisk together the milk, eggs, and vanilla extract. This mixture should be at room temperature to help the batter combine smoothly.
With the mixer on low speed, gradually add one-third of the milk mixture to the dry ingredients. Once added, increase the mixer speed to medium and beat until the batter is light and fluffy, which should take about 1 to 2 minutes.
Continue adding the remaining milk mixture gradually, mixing until well combined. Don't forget to stop and scrape down the sides of the bowl to ensure everything is incorporated evenly.
Divide the batter among the prepared cake pans, filling each with about 2 cups (470 grams). Make sure the batter is evenly distributed to ensure uniform baking.
Place the pans in the preheated oven and bake until a wooden pick inserted in the center comes out clean, which should take about 25 minutes. Keep an eye on them, as oven temperatures can vary.
Once baked, let the cakes cool in the pans on wire racks for 10 minutes. Then, carefully remove them from the pans and let them cool completely on the wire racks. This cooling step is crucial for a well-structured cake.
After the cakes are fully cooled, spoon 1 cup (220 grams) of Vanilla Buttercream into a pastry bag and cut a ¼-inch opening in the tip. Level the cooled cake layers if necessary, ensuring they stack evenly.
Place one layer of cake on a serving plate. Spread ¼ cup (55 grams) of Vanilla Buttercream in a thin layer on top. Use the pastry bag to pipe a small border of buttercream around the edge to create a dam.
Spread half of the lemon curd within this dam. This adds a burst of flavor and moisture to the cake.
Top with the second cake layer and repeat the process: spread ¼ cup (55 grams) of buttercream on top, pipe a border, and fill with the remaining lemon curd.
Finally, place the last cake layer on top and spread the remaining buttercream on the top and sides of the cake. Feel free to be creative with your frosting technique!
For the finishing touch, garnish with poppy seeds and lemon twists if desired. Refrigerate the cake for 30 minutes before serving. This helps set the layers and makes slicing easier.
Store any leftovers in an airtight container in the refrigerator for up to 3 days, though I doubt there will be much left!
