Step 1

Preheat oven to 350 degrees and lightly spray a 9x13 pan with non-stick spray. Set aside.

Step 2

Combine softened butter and sugar in a bowl and beat until well combined.  I used a hand mixer but you can mix it by hand or with a stand mixer.  Add mashed bananas, eggs, vanilla and sour cream, mix to combine.

Step 3

Add flour, baking powder, salt and stir until just combined {don't over mix}.  Pour into the bottom of the greased 9x13 pan.

Step 4

In a small bowl combine all of the crumb mixture ingredients.  Work the mixture together into small crumbs using a fork.  Don't over work the mixture or you will get a paste and it will change the texture of the bread.  Sprinkle the crumbs in an even and thick layer over the top of the banana bread batter.  Bake for 35-40 minutes or until a toothpick inserted in the center comes out with only a few moist crumbs or is clean.  Serve warm or cool and cover.  Store at room temperature for up to 3 days.