1-How to Prepare the Perfect Blueberry Lemon Cake: Baking a blueberry lemon cake doesn’t have to be complicated, and this guide walks you through each part with ease. Start by preheating your oven to 350°F and preparing your pans, which sets the stage for even baking and a professional finish. Butter and flour three 6-inch round cake pans, and if you want flat layers, wrap them with damp fabric strips as an optional step.

2-Preparing the Wet Ingredients: In a medium bowl, beat together 120 ml whole milk, 120 g sour cream, 3 egg whites, 3 tablespoons fresh lemon juice, 1 tablespoon lemon zest, and 1 tablespoon vanilla extract until well combined; set this mixture aside for later.

3-Mixing the Dry Ingredients: Sift 2 cups (240 g) all-purpose flour, 1⅝ cups (333 g) granulated sugar, 1½ teaspoons baking powder, and ¼ teaspoon kosher salt into a bowl. Take 1 tablespoon of this flour mixture and toss it with 1⅓ cups (180 g) fresh blueberries to coat them, which helps prevent sinking during baking.

4-Combining and Baking: Beat ¾ cup (170 g) softened unsalted butter until creamy, then add the sifted dry ingredients at low speed until it looks like sand. Gradually mix in the wet ingredients until the batter is fluffy, and gently fold in the coated blueberries. Divide the batter evenly among the prepared pans and bake for about 30 minutes, or until the centers spring back when touched. Let the cakes cool in the pans for 15 minutes before moving them to wire racks.

5-Making the Reduction and Buttercream: For the reduction, freeze ½ cup of fresh blueberries first. In a saucepan, cook the remaining 1 cup of fresh blueberries with 1 tablespoon granulated sugar, 1 tablespoon fresh lemon juice, and 1 tablespoon water until the berries burst; mash them and simmer until reduced by half, then strain and chill. For the buttercream, beat 1½ cups (340 g) unsalted butter and ¼ teaspoon kosher salt until fluffy, gradually add 6 cups (720 g) confectioners’ sugar, and mix in 3 tablespoons fresh lemon juice for the right taste and consistency. Blend the reduction into about 1 cup of the buttercream for a fruity twist.

6-Assembling the Cake: To assemble, pipe a thick ring of lemon buttercream around the edges of one layer and fill the center with blueberry-mixed buttercream; repeat for each layer. Frost the sides and top with lemon buttercream, opting for a naked look if you prefer. Finish by piping dollops of lemon buttercream around the top edge, adding the frozen blueberries inside, and refrigerate for 20 minutes before slicing. The total preparation time is about 30 minutes prep, 35 minutes cook, 35 minutes cool, for around 1 hour 40 minutes overall.