Directions

1. Generously butter an 11 ½” or 11 ¾” cast iron skillet (measured from across the top of the skillet, not the bottom). Don’t use a smaller skillet or the cake will overflow. Preheat oven to 350°F.
2. In a small bowl, mix together the oats and buttermilk and let stand for 10 minutes while you gather the ingredients for the rest of the cake.
3. On medium-high speed, cream the butter with the granulated sugar and brown sugar for 2 minutes. Add the eggs, one at a time, beating for about 30 seconds after each addition. Add the vanilla. Then beat in the buttermilk-oat mixture.
4. Whisk together the flour, baking powder, baking soda, and salt. Add the flour mixture alternately with the mashed bananas, in three additions, beginning and ending with the flour. Transfer to the greased skillet and bake for about 40 minutes, or until a toothpick inserted into the centre comes out clean. Remove cake from oven to a wire rack and let cake stand for several minutes while you prepare the topping.

Broiled Rum Frosting

1. Turn oven to broil mode. Mix all the topping ingredients together and spread over the hot cake. Place the cake about 3” from broiler element and broil until bubbly. Watch carefully so the nuts don’t burn. It will only take about 1 minute to broil the frosting. Immediately remove the cake to a wire rack and let cool.