Preheat oven to 400 degrees F. Line muffin tins with 16 paper muffin liners.
In a large bowl whisk egg, yogurt, milk, vanilla, and vegetable oil until smooth
Add flour, sugar, chocolate chips, cocoa powder, salt and baking soda
Scoop mixture into prepared muffin cups, about 2/3 full in each muffin cup.
Bake in preheated oven until a toothpick inserted into the center comes out clean, approximately 15-19 minutes. Cool in the pans for 10 minutes before removing to cool completely on a wire rack.