Step 1: Preheat and Prepare
Preheat the oven to 350°F (175°C).
Grease and line a 9x5 loaf pan with parchment paper.
Step 2: Mix the Dry Ingredients
In a large bowl, combine oats, flour, baking powder, baking soda, cinnamon, and salt. Set aside.
Step 3: Mix the Wet Ingredients
In another bowl, mash bananas, then whisk in sugars, eggs, melted butter, milk, and vanilla.
Step 4: Combine Wet and Dry
Add the dry ingredients to the wet ingredients and mix until just combined. Do not overmix.
Step 5: Bake
Pour the batter into the prepared loaf pan and smooth the top.
Bake for 60 minutes, or until a toothpick comes out clean.
Step 6: Prepare the Coffee Icing
In a small saucepan, melt butter and mix in coffee, vanilla, and powdered sugar. Stir until smooth.
Step 7: Drizzle and Cool
Let the banana bread cool for 10 minutes.
Drizzle the coffee icing over the warm bread.