My Family's Favorite Recipe for Banana Nut Muffins

Ingredients

• 3 ripe bananas, mashed
• 1/3 cup unsalted butter, melted
• 1 teaspoon vanilla extract
• 2 large eggs, beaten
• 1 cup granulated sugar
• 1 teaspoon baking soda
• 1/4 teaspoon salt
• 1 1/2 cups all-purpose flour
• 1/2 cup walnuts or pecans, chopped (optional)