Pineapple Upside-Down Cake

steps

1. Preheat oven to 350 degrees. Line a 10-inch round pan with parchment paper and grease with butter.  
2. Pour caramel into prepared cake pan. Arrange fruit atop caramel. Mince any leftover pineapple and spread over pineapple slices. Set aside. 
3. In a stand mixer fitted with paddle attachment, cream butters and sugars on medium speed until light and fluffy. Add cardamom, vanilla bean, zest, and ginger and mix to incorporate. With mixer on medium speed, slowly add yolks. 
4. In a medium bowl, combine dry ingredients. In another bowl, combine vanilla extract, buttermilk, and pineapple juice.
5. In two to three stages, alternately add the dry and wet ingredients into the creamed butter-sugar mixture on low speed, occasionally stopping to scrape sides of bowl. Begin and end with dry ingredients. Set aside. 
6. In a clean mixer bowl, whip egg whites slowly at first, then gradually increase the speed to medium-high after you achieve soft peaks. When whites form medium peaks, remove from mixer and fold into reserved cake batter in two stages. Make sure there are no streaks of white in the batter. Pour batter over caramel and fruit in prepared cake pan. Smooth with offset spatula to even the top.
7. Bake at 350 degrees until golden brown and the cake is done, about 20 to 30 minutes. Remove from oven and allow to cool for 10 minutes before running an offset spatula around the exterior of cake and inverting it onto a plate.

Caramel Sauce

4 tablespoons butter
5 ounces brown sugar
½ teaspoon vanilla bean seeds
¼ teaspoon salt

Heat skillet or sauce pan over medium heat and melt butter, then add sugar, vanilla, and salt. Avoid stirring; instead, tilt pan to move melting sugar. Set up an ice bath to shock hot pot holding caramel. When caramel turns dark amber, remove from heat and shock in ice bath for 10 seconds.

From Redux: Pineapple Upside-Down Cake.