Preheat the oven to 375 degrees F.
In a large mixing bowl, add all ingredients except for the bananas. Mix the ingredients together. Using a spatula, gently stir the mashed bananas into the batter. Transfer the batter into a large pouring measuring cup.
Add cupcake/muffin liners to a muffin tin. Pour the batter into the muffin liners filling each one two thirds full.
Bake in a preheated oven until a toothpick comes out clean when inserted in the middle of a muffin (about 20 minutes).
Carefully transfer the muffins to a cooling rack. Let cool before frosting them.
Top each muffin with frosting and add candy sprinkles (optional) right after frosting each muffin so that they’ll stick.