To make banana bread, preheat the oven to 350 degrees and grease the loaf pans. In a bowl, mix eggs, banana, sugar, oil, and yogurt. Add flour, cinnamon, baking powder, and salt, being careful not to overmix.
Make the topping by combining flour, brown sugar, and cinnamon, and then add butter to form crumbs. Pour the batter into the pan(s), sprinkle the topping, and bake for 45 minutes for mini loaves or 60 minutes for a large pan.