Preheat oven to 350°.
Mix the sour cream, butter and cream cheese in a large bowl.
Add in the corn bread mix and corns and mix well.
Add the green chiles and 1 1/2 cups cheese and mix well.
Pour into a well greased 9x13 inch pan.
Bake for 40-45 minutes, until toothpick inserted in the center comes out clean.
Sprinkle the remaining 1/2 cup of cheese over the casserole and bake 5-10 minutes longer, until the cheese is melted.
Cool for 5 minutes before cutting.