1. Preheat oven to 350°F (175°C). Grease and line an 8-inch cake pan with parchment paper.

2. In a bowl, whisk together flour, baking powder, and salt. Set aside.

3. In a separate bowl, beat eggs and sugar until light and fluffy.

4. Gradually add vegetable oil, milk, lemon zest, and vanilla extract to the egg mixture, mixing gently.

5. Fold in the dry ingredients carefully to maintain the airy texture.

6. Pour batter into the prepared pan and bake for 25–30 minutes, or until a toothpick inserted comes out clean. Let the cake cool completely.

7. In a chilled mixing bowl, whip heavy cream with powdered sugar, vanilla extract, and lemon juice until stiff peaks form.

8. Slice the cooled cake in half horizontally, spread half of the Chantilly cream on the bottom layer, then place the top layer and cover the cake with remaining cream.

9. Decorate with additional lemon zest or fresh berries if desired.

10. Chill in the refrigerator for at least 1 hour before serving.