Open your pineapple can. Drain pineapple well, reserving the syrup for the glaze.
In a mixing bowl, whisk the Bisquick, all-purpose flour and baking soda together. Set aside.
In another mixing bowl, cream the sugar, sour cream, softened butter and vanilla extract together for about 2 minutes on medium-high speed. Add the eggs and Rum, beat for 1 minute. Then, incorporate the dry ingredients and beat for an additional minute. Fold in your pineapple chunks.
Pour your preparation into your Flexipan®. Flatten with your spatula.
BAKE!
Bake for 45 minutes at 350F/180C. (Every oven heats differently, monitor your cake from 40min). It is ready when the toothpick inserted comes out clean.
RUM GLAZE PREPARATION
While your Cake is baking, prepare the Rum glaze.
Combine the sugar, butter, and reserved syrup in a medium saucepan. Stir over low heat until sugar is dissolved and butter is melted. Remove the saucepan from the heat and add the rum. Set aside. IMPORTANT: Remember that the glaze needs to be cooled at room temperature when it's being poured onto your cake. Otherwise it will go straight to the bottom.
Once your Bisquick Pineapple cake is out of the oven, spoon half the glaze over the cake while still in the mold. Let it cool down for about 10min. Then, Unmold and spoon the remaining glaze over your cake. Serve when it has completely cooled down. Enjoy & Bon Appétit!