11/2 cups all-purpose flour (spooned and leveled)
2 teaspoons baking powder
1/4 teaspoon salt
6 tablespoons unsalted butter, room temperature, plus 3 tablespoons (cut into small pieces) for preparing the top
1 cup sugar, plus 2/3 cup for preparing the top
2 large eggs
1 teaspoon vanilla extract
1/2 cup milk
7 thin rounds cored pineapple
- Preheat oven to 350°. In a large bowl, combine flour, baking powder, and salt; set aside.
- With an electric mixer, cream 6 tablespoons butter and 1 cup sugar until light and fluffy. Add eggs and vanilla; beat until combined. Add flour mixture in three additions alternately with the milk in two, beginning and ending with the flour. Mix just until combined.
- In a 10-inch cast-iron (or ovenproof nonstick) skillet, pour the remaining 2/3 cup sugar into skillet, and place over medium heat.
- Let sugar begin to liquefy, then stir with a wooden spoon until sugar is fully melted and golden, 2 to 3 minutes. The sugar may smoke, but if it browns too quickly, remove pan from heat briefly before continuing.
- Remove pan from heat; add 3 tablespoons butter (cut into small pieces), stirring to incorporate. The butter will help cool the caramel and stop it from darkening; it also thins out the caramel to make a syrupy sauce.
- Begin by placing one pineapple round in the center of the pan. Arrange the remaining rounds in a circle around center slice, overlapping slightly if necessary to fit.
- Carefully spoon batter over pineapples in skillet. Bake until a toothpick inserted in the center comes out clean, about 45 minutes. Let cake cool in pan 5 minutes. Run a knife around edge of cake, then carefully invert onto a platter. Serve warm or at room temperature.