Banana Bread With Variations

Name: Banana Bread With Variations
Ingredients: 1 stick butter, melted, plus softened butter for greasing; 2 cups flour; 1/2 teaspoon salt; 1 1/2 teaspoons baking powder; 1 cup sugar; 3 very ripe bananas, mashed with a fork until smooth; 2 eggs; 1 teaspoon vanilla extract; 1/2 cup chopped walnuts (optional); 1/2 cup shredded unsweetened coconut (optional)