Start by heating your oven to 350°F. Grab a 9×5-inch loaf pan and give it a light coat with nonstick cooking spray.
In a large mixing bowl, use a stand mixer or a hand mixer to cream together the softened butter and coconut sugar until it's light.
Crack in the eggs, add the mashed bananas, buttermilk, and vanilla extract. Mix until everything is well combined.
In a large mixing bowl, use a stand mixer or a hand mixer to cream together the softened butter and coconut sugar until it's light.