Preheat oven to 400 degrees F. Spray muffin tins with cooking spray. Combine meatball ingredients in a large bowl and mix thoroughly. Form into balls, each ~1 ounce (golf ball size) and place in muffin tin. Bake ~20-25 minutes until golden brown.
Meanwhile, combine yogurt ingredients in a bowl and mix well.
Serve meatballs and yogurt together.