- 1/2 cup butter, at room temperature
- 1 cup granulated sugar
- 2 tablespoons brown sugar
- 2 eggs
- 1 1/3 cups mashed bananas (2 to 3 whole bananas)
- 2/3 cup buttermilk
- 2 1/3 cup flour
- 1 teaspoon baking soda
- 3/4 teaspoon salt
- 3 ounces dark chocolate, melted
Adjust rack to the bottom third of the oven. Preheat oven to 350° F. Butter an 8- by 4-inch loaf pan.
Beat together butter and sugars on medium speed for about 2 minutes, until light and fluffy. Beat in eggs, one at a time, for 1 minute each. Add mashed bananas and beat until fairly smooth (some chunks might remain). Mix in buttermilk. Stir in flour, baking soda and salt until no white streaks of flour remain.
Using a spatula, fold in melted chocolate with just a few broad strokes; you want lots of big streaks. Pour batter into the prepared pan and bake until a tester comes out clean, 60 to 75 minutes.
Eat within 3 days, or bread can be sliced and frozen for up to 1 month.