Bananas Foster Upside-Down Cake

Preheat oven to 350 degrees F.

Melt butter in a 9-inch cast-iron skillet over medium heat. Remove from heat and stir in brown sugar and rum. Return to medium heat and bring to a simmer. Cook, stirring often, for 2 minutes. Remove from heat. Arrange banana pieces, cut-side down, over the brown sugar mixture and sprinkle with pecans.

Combine all-purpose flour, whole-wheat flour, baking powder, salt and cinnamon in a large bowl. Whisk egg, granulated sugar, yogurt, oil and vanilla in a medium bowl. Gradually add the wet mixture to the dry ingredients, whisking until just combined (the batter will be lumpy). Carefully spread the batter over the bananas.

Bake until a skewer inserted in the center comes out clean, about 20 minutes. Cool in the pan on a wire rack for 10 minutes. Run a knife around the edges to loosen. Invert the cake onto a serving plate, spooning any toppings left in the pan over the cake.