Directions

1. Prepare fruit layer: Cut plums into quarters; remove pits. Heat butter in a large saute pan over medium heat until it sizzles. Add plums; cook 2 to 3 minutes, until well coated and shiny.
2. Add sugar and cinnamon, and stir to coat plums. Cook, stirring frequently, until plums soften, 10 to 15 minutes.
3. Remove fruit with a slotted spoon, and transfer to a baking sheet to cool slightly. Remove pan from heat, saving syrup.
4. Butter and flour a 9 1/2-by-2-inch round cake pan. Arrange fruit, with cut edges down, in concentric circles starting with outside edge of pan. Fit leftover fruit into any spaces that remain.
5. Return syrup to medium heat, and boil until very thick with large bubbles. Immediately pour over fruit. Let cool.
6. Prepare cake: Heat oven to 350 degrees. Sift together flour, baking powder, and salt. Stir in cornmeal with a fork.
7. Place butter in the bowl of an electric mixer. Crumble in almond paste, and beat with the paddle attachment. Gradually add 3/4 cup sugar, and beat until creamy.
8. Add egg yolks, and beat until well combined. Beat in extracts. Add dry ingredients alternately with milk, beginning and ending with dry ingredients. Set aside.
9. In a clean bowl, whip egg whites until foamy. Gradually sprinkle in 2 tablespoons sugar, and beat until soft peaks form. Add a third of the whites to batter, and mix with a whisk. Gently fold in remaining whites.
10. Spread batter over fruit, and bake until a toothpick inserted in center comes out clean, about 1 hour. Let cool in pan.
11. Just before serving, place pan over low heat for 1 minute to ease unmolding. Run a knife around edges to loosen, and invert onto a serving plate.