Combine eggs and sour cream. Pour into at 9x13 baking dish sprayed with cooking spray. Bake 10-12 minutes or until set, but not firm.
Cook and drain sausage. Add mushrooms and chilies to pan; cook for 1-2 minutes.
Spoon mixture over eggs, sprinkle with cheese. Bake at 400 for 10-15 minutes or until golden brown.
VARIATION: Ham can be used in place of the sausage, if desired.