Pineapple Upside-Down Cake

Don't remember where I found this recipe, but after making it I quite enjoyed it. Definitely best at room temp or warm.

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Pineapple Upside-Down Cake
Adapted from Gourmet, February 2000

Topping:
1/2 medium pineapple, peeled, quartered lengthwise, and cored
3/4 stick unsalted butter
3/4 cup packed light brown sugar

Batter:
1 1/2 cups all-purpose flour
2 teaspoons baking powder
1/4 teaspoon salt
3/4 stick unsalted butter, softened
1 cup granulated sugar
2 large eggs
1 teaspoon vanilla
1 tablespoon dark rum
1/2 cup unsweetened pineapple juice
2 tablespoons dark rum for sprinkling over cake

Special equipment: a well-seasoned 10-inch cast-iron skillet.
If you lack a cast-iron skillet of this size, make the caramel
in a small pot and scrape it into the bottom of a similarly-sized cake pan.

Preheat oven to 350°F.

Make topping: Cut pineapple crosswise into 3/8-inch-thick pieces.
Melt butter in skillet. Add brown sugar and simmer over moderate heat,
stirring, 4 minutes. Remove from heat. Arrange pineapple
on top of sugar mixture in concentric circles, overlapping pieces slightly.

Make batter: Sift together flour, baking powder, and salt.
Beat butter in a large bowl with an electric mixer until
light and fluffy, then gradually beat in granulated sugar.
Add eggs, 1 at a time, beating well after each addition.
Beat in vanilla and rum. Add half of flour mixture and beat
on low speed just until blended. Beat in pineapple juice,
then add remaining flour mixture, beating just until blended.
(Batter may appear slightly curdled.)

Spoon batter over pineapple topping and spread evenly.
Bake cake in middle of oven until golden and a tester comes
out clean, about 45 minutes. Let cake stand in skillet 5 minutes.
Invert a plate over skillet and invert cake onto plate
(keeping plate and skillet firmly pressed together).
Replace any pineapple stuck to bottom of skillet.
Sprinkle rum over cake and cool on plate on a rack.

Serve cake just warm or at room temperature.

Cake may be made 1 day ahead and chilled, covered.
Bring to room temperature before serving.