Healthy Chocolate Banana Brownies

Name: Healthy Chocolate Banana Brownies
Ingredients: 2 ripe bananas, mashed; ¼ cup maple syrup (or honey); ¼ cup coconut oil (or Greek yogurt); 1 teaspoon vanilla extract; 1 egg (or flax egg for vegan); ½ cup unsweetened cocoa powder; ½ cup oat flour (or almond flour for gluten-free); ½ teaspoon baking soda; ¼ teaspoon salt; ⅓ cup dark chocolate chips (plus extra for topping)