Preheat your oven to 350°F. Grease a 9" x 5" pan.
Whisk the flour, baking soda, and salt in a bowl. In another bowl, mix the coconut sugar, butter, eggs, and Greek yogurt.
Gently fold the mashed bananas into the wet mixture. Blend in the dry ingredients.
Gradually mix the dry ingredients into the wet mixture on low speed, just until it's combined and moist. Do not overmix.