Preheat oven to 350°F (177°C). Grease a 9×5-inch loaf pan with nonstick spray. Set aside.
In a large mixing bowl, whisk together the flour, cocoa powder, baking soda, and salt until well combined. Stir in ¾ cup (135g) of chocolate chips, then set the mixture aside.
Using a handheld or stand mixer fitted with a paddle or whisk attachment, beat the butter and sugar together on high speed for about 3 minutes until smooth and creamy. With the mixer running on medium speed, add the eggs one at a time, beating well after each addition. Mix in the yogurt, mashed bananas, and vanilla extract until fully combined. Add the dry ingredients and hot water, then beat on low speed just until everything comes together. The batter will be thick—avoid overmixing.
Pour and spread the batter into the prepared baking pan. Sprinkle remaining chocolate chips on top, down the center of the loaf.
Bake for 60–65 minutes, covering the top loosely with aluminum foil halfway through to keep it from drying out. The bread is ready when a toothpick inserted into the center comes out mostly clean, with just a few moist crumbs. Ovens vary, so start checking for doneness around the 60-minute mark and continue checking every 5 minutes until it’s perfect.
Remove the bread from the oven and allow it to cool in the pan set on a wire rack for at least 1 to 2 hours before removing, slicing, and serving.
Cover the bread tightly and store it at room temperature for up to 5 days, or keep it in the refrigerator for up to 1 week. Banana bread actually tastes even better on the second day, once the flavors have had time to blend and deepen.
