Cake:
1 1/2 cups all purpose flour
6 Tbsp cake flour
6 Tbsp of ground almonds (from about 2 oz of whole almonds)
3/4 teaspoon baking powder
1/2 teaspoon salt
1 3/4 cups of sugar
1 cup (2 sticks) unsalted butter at room temperature
4 large eggs
3/4 teaspoon vanilla extract
3/4 cup sour cream

Directions:
1 Start by making the caramel topping. *Take brown sugar and butter and combine and melt in a saucepan on medium heat until sugar dissolves and the mixture is bubbly, this should take several minutes. Pour mixture into a 10 inch diameter stick-free cake pan with 2 inch high sides. Arrange pineapple slices in a single layer on top of the caramel mixture.
2 Preheat oven to 325 degrees F. Whisk the flours, almonds, baking powder, and salt in a large mixing bowl. In a separate bowl, use an electric mixer to beat the sugar and butter together until light. Add eggs one at a time, beating after each addition. Beat in the vanilla. Add dry ingredients alternately with sour cream in 2 additions each, beating well after each addition. Pour cake batter over caramel and pineapple in pan.
3 Bake cake until tester inserted into the center comes out clean, about 1 hour to 1 hour 15 minutes. Cool cake in pan on a rack for 10 minutes. Turn cake out onto a platter. Serve warm or at room temperature.