What’s for dinner?

1 cup baking mix (we use Bisquick) 1 cup milk 4 T mayonnaise, divided 1 lb. hot ground sausage ½ cup onion, chopped 1 egg 2 cups cheddar cheese, shredded 2 (4oz) cans chopped green chilies Combine baking mix, milk and 2 T mayonnaise in a small bowl, mix well.