Roti Pisang Kotak Coklat

Bahan-bahan (3 porsi)

• 3 large overripe bananas, mashed
• 1/4 cup buttermilk
• 2 teaspoons vanilla extract
• 2 cups flour
• 1 teaspoon baking soda
• 3/4 teaspoon baking powder
• 1 teaspoon cinnamon
• 1/4 cup unsweetened cocoa powder
• 3 -5 tablespoons boiling water
• 9 tablespoons butter
• 1 cup sugar
• 2 large eggs