Step 1

Preheat the oven to 350F.

Step 2

In a large bowl, mash bananas and stir in melted butter.

Step 3

Add the sugar, egg, and vanilla and stir.

Step 4

Add the baking soda and salt and mix.

Step 5

Mix in the flour (and xanthan gum).

Step 6

Fold in the "addition" ingredient.

Step 7

Pour mixture into a 4"x 8" greased loaf pan (or line it with parchment paper) and bake for 1 hour.

Step 8

Cool in pan for five minutes and then cool on a rack.