Preheat oven to 350˚F.
Place the butter in a large microwave-safe bowl and melt by heating 15-30 seconds in the microwave.
Add the bananas into the butter and use a fork to mash the bananas. Then mix them into the butter.
Add the sugar, eggs, and vanilla to the banana mixture and stir until smooth.
Add the flour, baking soda and salt, then stir until the flour is just combined.
Transfer the mixture into a large greased loaf/bread pan (9.25 long x 5.25 wide x 2.75 deep).
Bake for 45-55 minutes or until a toothpick comes out clean.
Let cool in the pan for 5 minutes, then remove from pan and finish cooling on a wire rack.
Slice into 8 slices.
