Preheat your oven to 350°F (175°C).
In a large mixing bowl, mash the ripe bananas until smooth.
In a separate bowl, combine the gluten-free flour, baking soda, and a pinch of salt. If using ground cinnamon, add it here.
Stir in the melted coconut oil and vanilla extract into the mashed bananas. Mix until well combined, then add sugar and eggs, stirring until smooth.
Gradually fold the dry ingredients into the wet mixture until no more flour is visible. If adding nuts, fold them in now.
Pour the batter into a greased 9x5-inch loaf pan and smooth the top.
Bake for 50-60 minutes, checking for doneness with a toothpick.
Let the banana bread cool in the pan for about 10 minutes, then transfer to a wire rack to cool completely.