Spray small nonstick saucepan with nonstick cooking spray. Combine all filling ingredients except sour cream in saucepan. Cook and stir over medium heat for 2 to 3 minutes or until thoroughly heated. Stir in sour cream. Remove from heat; cover to keep warm.
Spray 8 to 10-inch nonstick skillet with sloping sides (omelet pan) with nonstick cooking spray. In small bowl, combine egg product and milk; blend well. Pour egg mixture into skillet. Cook over medium heat without stirring, running spatula around edge of skillet and lifting egg mixture to allow uncooked portion to flow to bottom of skillet. Cook 3 to 4 minutes or until mixture is set but top is still moist.
Spoon filling over half of omelet. Sprinkle 2 tablespoons of the cheese over filling. With spatula, loosen edge of omelet and fold other half over filling. Sprinkle with remaining 2 tablespoons cheese. Cover; cook 1 minute.