1/2cup(100g) brown sugar (light or dark as you please)
20ouncecan pineapple slices, drained
For the cake:
1/2cup(113g) butter, softened to room temperature
3/4cup(150g) white granulated sugar
2large eggs, at room temperature
1teaspoonpure vanilla extract
1 1/2cups(190g) self-rising flour* (sift first if not measuring by weight)
Preparing the pineapple topping:
Center the oven rack, and preheat the oven to 350°F. In a well-seasoned 10-inch-diameter cast-iron skillet, melt the 1/2 cup butter over medium heat. Off heat, immediately sprinkle the brown sugar over the melted butter. Arrange 7 pineapple slices in the skillet. Set aside.
Making the cake batter:
Put the 1/2 cup softened butter, the white sugar, and the eggs in a large mixing bowl. Use electric hand-held beaters to cream the mixture until it is light and fluffy -- about 3 minutes. Use a spatula to stir in 1/3 of the self-rising flour. Then stir in half of the milk. Repeat with another 1/3 of the flour and the remaining milk. Then stir in the remaining flour. Briefly beat with the electric beaters until all ingredients are thoroughly combined -- not more than 30 seconds.
Assembling and baking the cake:
Spoon the batter over the pineapples in the skillet, and gently smooth the top with the back of the spoon. (Don't worry if some of the melted butter creeps up over the batter.) Bake in the preheated oven until the cake puffs and lightly browns -- usually 30 minutes.
Unmolding the cake:
While the cake is still hot, run a knife between the edge of the cake and the wall of the skillet. Place a large plate or platter on top of the skillet. Then, being sure to protect your hand from the hot handle, invert to unmold.
Although the cake is wonderful at any temperature, it is particularly delicious when served warm. Enjoy it with champagne for dessert, or with coffee for breakfast!
TO MAKE YOUR OWN SELF-RISING FLOUR: For each cup of all-purpose flour, add 1 1/2 teaspoons baking powder, and 1/2 teaspoon salt. Whisk to combine.