Preheat your oven to 350°F and grease a 9-inch round cake pan with butter, then dust it lightly with flour. I do this step first because rushing it while your batter sits means oxidation starts breaking down those precious lemon oils you spent two minutes zesting.
Cream together the unsalted butter and granulated sugar for exactly three minutes using an electric mixer on medium speed. Your mixture should look pale and fluffy—when you lift the beaters, ribbons should fall back into the bowl. This aeration creates the structure that holds those blueberries suspended throughout your beautiful summer lemon blueberry cake recipe.
Add eggs one at a time, beating for 30 seconds between each addition and scraping down the bowl's sides. I confess I used to skip the scraping part and wondered why my beautiful layer cake sometimes had dense pockets—the unmixed egg whites create texture inconsistencies that ruin elegance.
Whisk together the flour, baking powder, and salt in a separate bowl before adding to your wet mixture. Alternate adding dry ingredients and the milk mixture in three additions, starting and ending with dry ingredients because this prevents overmixing that toughens your crumb structure.
Stir in the lemon zest, fresh lemon juice, and honey until just combined—no more than 10 strokes of your spatula. This is when your batter reaches the exact thickness needed to cradle those blueberries, the moment most recipes miss entirely.
Gently fold in your fresh blueberries using an underhand scooping motion rather than stirring, which bruises the berries and stains your beautiful summer lemon blueberry cake recipe with purple streaks. The batter should feel thick enough that berries nestle in without sinking—test by placing one berry on top and watching it settle slowly.
Pour the batter into your prepared pan and smooth the top with an offset spatula, then place in your preheated oven. Bake for 40 minutes until a toothpick inserted near the center emerges with just two or three moist crumbs clinging to it—not wet batter, just the slightest hint of moisture.
Cool in the pan for 15 minutes before turning out onto a wire rack to cool completely. This resting period lets the crumb set enough to handle without deflating, which is why rushing directly to frosting sometimes creates an elegant lemon cake that falls apart under the knife.