Instructions:

Preheat oven to 375 degrees F. Line muffin tins with paper or foil cups. Mash bananas in a medium bowl, leaving some small chunks. Stir in egg, sour cream and melted butter. In a large bowl combine the sugar, flour, baking soda and salt. In a small, microwave-safe bowl, melt chocolate baking bar in the microwave on high power for 45 seconds. Stir. If un-melted pieces remain continue microwaving and stirring the chocolate in ten-second intervals until it is all melted and smooth; set aside. Pour the banana mixture into the dry ingredients and stir just to combine. The batter should be lumpy. Stir in melted chocolate, 1/2 cup of mini chocolate chips, and vanilla. Divide batter among the prepared muffin cups and sprinkle each with the additional 1/4 cup mini chocolate chips for the topping. Bake at 375 degrees for 15 to 20 minutes. Muffins are done when the tops of the muffins look dry and cracked. Because of the melted chocolate chips in the muffins the traditional toothpick test may not be reliable.

Tip: Use an ice cream scooper for an easy way to fill muffin cups.

Serving Suggestions: For a different look, instead of the mini chocolate chips for the topping try chopped walnuts or pecans, or dust with powdered sugar after baking. You can create an attractive platter of Dark Chocolate Banana muffins with a variety of different toppings in the same batch.
Nutrition Information Per Serving:

Nutrition Information Per Serving: Calories 270; Total Fat 15 g (Sat 8 g, Trans 0 g, Poly 0 g, Mono 1 g); Cholesterol 35 mg; Sodium 35 mg; Potassium 115 mg; Total Carbohydrates 37 g; Dietary Fiber 2 g; Total Sugars 25 g; Protein 4 g. Percent Daily Value: Vitamin A 4%; Vitamin B6 4%; Vitamin C 4%; Vitamin D 0%; Calcium 2%; Iron 6%.