Gluten-Free Caramelized Pineapple Upside-Down Cake

The rum will ignite when you tilt the mold, and the alcohol will evaporate.
Preheat the oven to 350 degrees.Combine the brown sugar, 2 tablespoons butter, and vanilla pods in a large skillet over medium-high heat; cook for 6 minutes or until the butter melts and the sugar dissolves, stirring frequently. Arrange the pineapples in a single layer. Gently pour the rum over the pineapple; tilt the pan until it is burnt. Simmer for 5 minutes on each side or until slightly soft and caramelized. Remove the vanilla pod.Brush a 9-inch cake pan with cooking spray. Place the pineapples in a single layer on the bottom of the pan; sprinkle the pineapple with the sugar mixture, tilting the pan to coat the bottom evenly.In a dry measuring cup, add all - purpose flour by weight or lightly spread with a spoon; flatten with a knife. Combine all-purpose flour, almond flour, baking powder, salt, and baking soda; whisk to combine. Melt the remaining 2 tablespoons of butter in a microwave-safe bowl over high heat for 35 seconds. Combine the melted butter, sour cream and vegetable oil in a bowl, stirring well with a whisk.Put the granulated sugar and eggs in a large bowl; beat with a mixer on high speed for 5 minutes or until fluffy. Reduce the speed to medium. Add the flour and sour cream mixture alternately to the egg mixture, starting and ending with the flour mixture. Spoon the batter onto the pineapple, spreading evenly. Bake at 350 ° C for 38 minutes or until a wooden stick inserted in the center comes out clean. Cool in the pan for 15 minutes on a wire rack. Use a knife to separate the cake from the edges of the mold; flip it onto a plate.