Preheat oven to 350 degrees F. Spray jumbo muffin pan with cooking spray; set aside.
In a medium sauce pan, add 5 tablespoons of butter over medium heat. Cook butter, while stirring constantly. The butter will foam up and then turn golden brown. Once the foam starts to diminish and your butter turns golden brown, take it off the heat and set aside.
In a medium bowl, add the flour, baking powder and salt. Mix together.
In a large mixing bowl add the sugar, 4 tablespoons of the browned butter and the egg. Whisk together. Whisk in milk and mashed bananas.
Using a ladle, stir in the dry ingredients until just combined.
Make the crumb topping: Stir together the brown sugar, flour, cinnamon and 3 tablespoons of cold butter. Mix until the mixture is crumbly and the butter resembles small pea size shapes.
Scoop 1/2 cup of banana bread mixture into each muffin tin. Top with crumb topping and chopped pecans.
Bake for 25-30 minutes, or until a toothpick inserted comes out clean.
Store in an air tight container. Muffins will keep for 3-5 days.
Enjoy!