Preheat oven to 375°.
Saute' onion and pepper in butter.
In a large bowl, fold both cans of corn into beaten eggs.
Add corn muffin mix to egg mixture.
Pour corn mixture into well greased 9x13" pan.
Stir in onion, pepper, butter, sour cream, and grated cheese.
Bake at 375° for 40 minutes, until set and golden.