Salted-Caramel Pineapple Upside-Down Cake

1 cup dark-brown sugar

2 sticks unsalted butter, at room temperature

3 tbsp. dark rum

1 ½ tsp. salt

1 ½ cups all-purpose flour

2 tsp. baking powder

½ tsp. ground cinnamon

1 cup granulated sugar

1 tbsp. vanilla extract

2 large eggs

½ cup whole milk

1 medium pineapple, peeled, cored, and cut into rings; 1 ring cut into chunks

Preparation:

Coat a 9-inch cake pan with cooking spray and set aside. In a small saucepan over medium heat, heat brown sugar and 1 stick butter, whisking occasionally, until sugar is dissolved. Bring to a boil and cook until caramel thickens and turns a deep brown, about 3 minutes. Remove from heat and whisk in rum and 1 teaspoon salt. Pour caramel into prepared cake pan and swirl around to coat. Set aside and let cool completely, at least 30 minutes.

Preheat oven to 350ºF. Meanwhile, in a medium bowl, whisk together flour, baking powder, remaining salt, and cinnamon. In a large bowl, using an electric mixer on medium, beat together granulated sugar and remaining butter until light and fluffy. Add vanilla; beat in eggs, 1 at a time. Reduce mixer speed to low and beat in half the dry-ingredient mixture and ¼ cup milk. Repeat with remaining dry-ingredient mixture and milk. Arrange pineapple rings atop caramel in cake pan. Fill in spaces between rings with pineapple chunks. Carefully pour batter over pineapple and smooth, using a rubber spatula. Bake until a toothpick inserted in the center comes out clean, about 50 minutes. Transfer pan to a wire rack and let cool for 30 minutes. Run a sharp knife around the sides of the pan to loosen the cake; invert onto a large serving plate. Serves: 8.