Prep Time: 30 minutes

Bake Time: 30–35 minutes

Cooling Time: About 1 hour

Yield: 10–12 servings

Pans: Two 8-inch or 9-inch round cake pans

Oven: 350°F (175°C)

Cake Layers

• 2½ cups (325g) all-purpose flour
• 2 teaspoons baking powder
• 1 teaspoon kosher salt
• 1½ cups (300g) granulated sugar
• 1 tablespoon lemon zest
• ½ cup (113g) unsalted butter, softened
• ⅓ cup neutral oil
• 3 large eggs
• 2 teaspoons vanilla
• ¾ cup whole milk or buttermilk
• 2 tablespoons fresh lemon juice
• 1½ cups fresh blueberries
• 1 tablespoon flour for the blueberries

Mascarpone Chantilly Cream

• 2 cups cold heavy whipping cream
• 8 ounces (226g) cold mascarpone
• ¾ cup powdered sugar
• 1½ teaspoons vanilla

Instructions

1. Preheat oven to 350°F (175°C) and prepare two round cake pans.
2. Rub lemon zest into the granulated sugar.
3. Beat butter and lemon sugar for 2–3 minutes.
4. Mix in the oil.
5. Add eggs one at a time, then vanilla.
6. Whisk flour, baking powder, and salt separately.
7. Mix milk and lemon juice together.
8. Alternate adding dry ingredients and milk mixture to the butter mixture, beginning and ending with the dry ingredients.
9. Toss blueberries with 1 tablespoon flour and fold gently into the batter.
10. Divide batter between pans.
11. Bake for 30–35 minutes.
12. Cool completely.
13. Whip heavy cream, powdered sugar, and vanilla to soft peaks.
14. Add mascarpone and whip just until stiff peaks form.
15. Spread frosting over the first cake layer and add fresh blueberries.
16. Add the second layer.
17. Frost the top and sides.
18. Garnish with blueberries and lemon if desired.
19. Refrigerate until serving.

Notes

Do not overmix the batter after adding flour. Use fresh lemon zest for the strongest flavor. Keep mascarpone and heavy cream cold. Stop whipping the frosting as soon as it holds stiff peaks. Chill the finished cake, then allow it to sit at room temperature briefly before serving for the softest texture.