Butterscotch Banana Cake without flour

1 cup all-purpose flour 1 teaspoon baking powder 1/2 teaspoon baking soda 1/2 teaspoon salt 1 cup quick-cooking oatmeal , uncooked 1/3 cup sugar or 1/3 cup[...]

1 2/3 cups butterscotch chips, divided (11 oz pkg) 1 (18 1/2 ounce) package yellow cake mix 4 large eggs 3/4 cup medium mashed banana 1/2 cup vegetable oil[...]

2 tablespoons raisins , soaked in 1/4 cup water 1/3 cup sugar 1 tablespoon butter 1/4 teaspoon salt 2 tablespoons rum (or more) 2 -4 scoops vanilla ice cream[...]