Preheat your oven to 350°F and prepare the loaf pan with butter or parchment paper.
Melt the butter over medium heat until it turns brown and releases a nutty aroma. Remove it and let it cool for 10 minutes.
Whisk the browned butter with both types of sugar for 1 minute. Add the eggs and whisk at high speed for 3 minutes until the mixture becomes frothy.
Add in the bananas and whisk them (the mixer should mash them, but you can also mash them yourself).
Mix the coffee with water and whisk it in.
Gently fold in the dry ingredients, then fold in the walnuts.
Transfer the batter to the loaf pan, decorate it however you like, and bake for about 45-50 minutes or until a toothpick comes out with moist crumbs attached.
Let it cool and serve! I personally love to warm a slice for 5-10 seconds and spread it with peanut butter. 🤤🤤