This cake was a favorite breakfast offering at the late Zefiro restaurant in Portland, often consumed with a latte in a bowl. It also makes a great afternoon snack and dessert.

Steps

1. Preheat the oven to 350 degrees. Butter and flour a 9-inch springform pan.
2. Cream together the butter and sugar until light and fluffy. Add the eggs, one at a time, and mix thoroughly between additions. Add the zest and almond extract.
3. In a separate bowl, mix the flour, ground almonds, and baking powder, then stir into the egg mixture until just blended.
4. Smooth the batter into the springform pan and distribute the grapes evenly over the batter, pressing them in lightly.
5. Bake for 50 to 60 minutes, until a toothpick or skewer inserted in the middle comes out clean or with tiny crumbs. Let cool, then invert onto a plate and dust lightly with powdered sugar.