Plum Upside-Down Cake

Directions

Preparation

1. Preheat the oven to 350°F. Grease a 9-inch round baking pan (I use vegetable shortening).
2. Combine the butter, brown sugar, and cinnamon in a small saucepan. Place over medium heat and cook until the butter is melted, stirring until smooth. Pour the mixture into the prepared cake pan, spreading to coat evenly.
3. Arrange the plum slices in a single layer in concentric circles over the brown sugar mixture. (I make one circle in the center and one around the edges.)
4. Stir together the flour, baking powder, and salt in a small bowl. Set aside.
5. Beat the granulated sugar and mayonnaise with an electric mixer until creamy. Add the eggs, one at a time, beating well after each addition. Add the flour mixture to the sugar mixture alternately with the milk, beginning and ending with the flour mixture. Beat in the extracts.
6. Pour the batter evenly over the plums. Bake the cake at 350°F for 40 to 45 minutes, until a toothpick inserted in the center comes out clean. Let cool in the pan for 5 minutes.
7. Run a knife around the edge and immediately turn out the cake onto a rimmed cake plate or platter. Serve warm or at room temperature.