Banana Espresso Chocolate Chip Muffins

Espresso and chocolate go so well together. Add bananas to the mix and you are talking about the most wonderful triumvirate of flavor.  
This recipe for Banana Espresso Chocolate Chip Muffins is from the Baked Cookbook (which I've mentioned quite a bit recently).  These little treats are an excellent way to start your day and a great way to turn those over-ripe bananas into something more delicious than compost mush.
Note:  Instant espresso powder is not the same as ground espresso - it dissolves instantly in hot water.

1 1/2 cups mashed, very ripe bananas (about 4 medium bananas)
1/2 cup sugar
1/4 cup firmly packed light brown sugar
1/2 cup (1 stick) unsalted butter, melted
1/4 cup whole milk
1 large egg
1 1/2 cups all-purpose flour
1 teaspoon instant espresso powder
1 1/2 teaspoons baking soda
1 teaspoon salt
1 cup (6 ounces) semisweet chocolate chips (I usually go with Ghiradelli.)
Yield: 12 muffins (Halving the recipe is simple, except for the egg part...)

Preheat the oven to 350 degrees.  Spray a 12-cup muffin pan with non-stick cooking spray.  (I take a paper towel and use the remaining melted butter from the saucepan to grease the muffin pan.)
In a medium bowl, stir together bananas, sugar, butter, milk and egg.
In another medium bowl, whisk together the flour, instant espresso powder, baking soda and salt.  Make a well in the middle of the dry ingredients.  Pour the wet ingredients into the well and stir until just combined.  Fold in the chocolate chips.
Fill each cup about three-quarters full.  Bake in the center of the oven for 20 to 25 minutes, until a toothpick inserted in the center of a muffin comes out clean.
Move the muffin pan to the cooling rack, and let cool for 15 minutes.  After 15 minutes, remove the muffins from the pan and let them finish cooling on the cooling rack.
Muffins can be stored in an airtight container for up to 2 days.