MAKES: One 9-inch cake (at least 8 servings)
TIME: About 1 hour
Juicy, ripe plums caramelize beautifully to create a rich, caramelized topping when the cake is inverted. Use a skillet if you want to maximize this browning effect. The touch of rosemary gives the cake a pleasant floral flavor, which complements the fruit.
Other fruit you can use: apples, blackberries, pitted cherries, cranberries, or apples.
8 tablespoons (1 stick) unsalted butter, melted
1/2 cup packed dark brown sugar
1 teaspoon finely chopped fresh rosemary leaves
4 or 5 ripe sweet plums, halved, pitted, and cut into chunks
1 cup buttermilk
2 eggs
1/2 cup sugar
2 cups all-purpose flour
1 teaspoon baking soda
1/4 teaspoon salt
Preheat the oven to 350В°F. Liberally grease a 9-inch round cake pan or cast-iron skillet with half of the butter. Sprinkle the brown sugar and rosemary evenly over the bottom of the pan and spread the plums in the pan in a single layer; set aside.
Whisk the remaining melted butter, buttermilk, eggs, and sugar together until foamy. In a separate bowl, combine the flour, baking soda, and salt. Gradually add the egg mixture to the flour mixture and stir until well incorporated.
Carefully spread the batter over the plums, using a spatula to make sure it’s evenly distributed. Bake until the top of the cake is golden brown and a toothpick inserted in the center comes out clean, 50 to 60 minutes. Let the cake cool in the pan for just 5 minutes.
Run a knife around the edge of the pan. Put the serving plate on the top of the cake pan and flip the pan so that the serving plate is now on the bottom and the cake pan upside down and on top. The cake should fall out onto the serving plate. If the cake sticks, turn it right side up and run the knife along the edge again, then use a spatula to lift gently around the edge. Invert the cake again and tap on the bottom of the pan. If any of the fruit sticks to the pan, don’t worry; simply use a knife to remove the pieces and fill in any gaps on the top of the cake. Serve warm with ice cream.
Variations
Fresh Pineapple Upside-Down Cake. Use the sweetest pineapple you can find: Omit the rosemary. Substitute six 1/2-inch-thick slices peeled fresh pineapple (see Preparing Pineapple), or as many as will fit in the pan, for the plums and 1/2 cup cornmeal for half the all-purpose flour.
Sweet Green Tomato Upside-Down Cake. Use вem if you have вem: Omit the rosemary. Substitute 6 or more thick slices green tomatoes for the plums and 1/2 cup cornmeal for half the flour if you like.
Pear and Almond Upside-Down Cake. Small Seckel pears look elegant, but full-size pears work too: Substitute 1/4 cup chopped almonds for the rosemary; 3 to 4 small ripe pears, peeled, cored, and halved, for the plums; and 1/2 cup ground almonds for half the flour. Mix 3 tablespoons almond paste in with the butter.