Preheat oven to 350 degrees. Lightly spray a 9 by 5 inch loaf pan with non-stick cooking spray.
In a large mixing bowl, mix the mashed bananas with the melted butter. Add the sugar, egg and vanilla and mix well. Add the salt, baking soda and sweet rice flour blend (in that order) and mix well. Add the nuts and stir. Pour batter into the prepared pan. Bake for 50-60 minutes or until a toothpick inserted in the center comes out clean. Let cool in the pan for 15 minutes and remove from the pan. Let cool completely on a wire rack or serve warm.