Mix together flour, sugar, cocoa and baking soda in a medium bowl
Add in egg, sour cream, milk, vanilla and oil and mix well
Stir in chocolate chips
Place mixture in greased muffin tins. Sprinkle a few mini chocolate chips on top of batter, if desired (purely for looks, but hey, what is another few chocolate chips?)
Bake at 375* for 15 minutes or until toothpick inserted in middle tests done
Remove from oven when done and let cool for 10 minutes. Remove from pan and place on cooling rack