Preheat oven to 350 F. Grease an 8x4-inch baking pan; set aside.
In a large bowl, stir together banana, yogurt, peanut butter, and vegetable oil until combined.
Add eggs, and stir until incorporated.
Stir in sugars until well-combined.
Add flour, cocoa powder, baking soda, and salt. Stir until just combined.
Stir in 1/4 cup chocolate chips.
Pour batter into pan, smoothing as needed.
Sprinkle remaining 1/4 cup chocolate chips over the batter
Bake for about 35-45 minutes, or until a toothpick inserted in the center comes out clean. It’s ok if it has some melted chocolate, but it shouldn't have any crumbs.
Let it cool for 5-10 minutes in the pan.
Run a thin knife around the edge of the pan to loosen the bread.
Remove from pan, and let cool on a wire cooling rack.