Preheat your oven to 325 F. Coat a 9″ loaf pan with butter or non-stick baking spray. (I used the Farberware 9″ loaf pan and coconut oil spray)
Whisk together the wet ingredients (egg, Greek yogurt, vegetable oil, honey, brown sugar, mashed bananas, and vanilla extract).
In a small bowl, add the dry ingredients (gluten-free flour, baking soda, cinnamon, salt).
Slowly pour the dry ingredient mixture into the wet ingredients, stirring constantly until mixed together with no clumps. Fold in dark chocolate chips.
Pour the mixture into your greased baking pan. On top, drizzle peanut butter. Bake for 60-70 minutes, or until a toothpick comes out clean.
Let cool for 20-30 minutes in the pan and then transfer the loaf to a cooling rack to cool completely.