Double Fudge Banana Muffins

Yes, again I had some ripe bananas that needed to be used.  So, I made these and they were quick and delicious!  And you don't even need a mixer for this.  It's all combined manually.  Enjoy!
-1 egg, beaten
-1/4 cup packed brown sugar
-1/3 cup sour cream
-1 tsp vanilla extract
-3 medium ripe bananas, mashed
-1 cup flour
-1/2 tsp baking soda
-1/2 tsp baking powder
-1/2 tsp salt
-1/4 cup unsweetened cocoa powder
-1 cup semi sweet chocolate chips
Preheat oven to 350 F.  Line 12 muffin cups with paper liners.  Set aside.
Combine all ingredients into one large bowl and gently mix by hand until well incorporated.  Scoop evenly into prepared cups.  
Bake in preheated oven for 20-25 minutes or until toothpick comes out clean.  Enjoy!