1. Preheat oven 350 degrees F.

2. In a large bowl, cream the butter and sugar with an electric mixer until well blended (about 5 minutes; the sugar will be slow to incorporate).

3. Beat in vanilla extract until fluffy and light (about 15 seconds).

4. Add egg, then milk, beating well between additions. It will be a thin batter.

5. In a smaller bowl, combined flour and baking powder with a wire whisk.

6. Add dry ingredients into batter in quarters, mixing quickly with the whisk after each addition. Stir in lime zest.

7. Pour batter into well-greased 13 X 9-inch cake pan. Distribute half the blackberries on batter.

8. Top with granulated sugar. Position pan on center rack of oven.

9. Bake for 20 minutes.

10. Remove from oven. The blackberries will have sunken and disappeared.

11. Top with remaining blueberries, and return to over.

12. Bake another 10-15 minutes, or until center of cake tests clean with a skewer.

13. Let cool before cutting into rectangles. Remove servings with spatula. Dust with powdered sugar.

14. Serve as is or with lime curd and/or clotted cream

Chef's Note & Story

Adapted from a Nigel Slater recipe