Grease a 9-inch square pan; line bottom of pan with wax paper.
Grease wax paper; set pan aside.
Beat sour cream and cream cheese at medium speed of an electric mixer until smooth and creamy; set aside.
Beat egg whites and cream of tartar at high speed of electric mixer until foamy; set aside.
Beat egg yolks at high speed until thick and pale.
Fold beaten egg whites into yolks; pour mixture into prepared pan.
Bake at 350° for 10 minutes or until set.
Broil 5 1/2 inches from heat (with electric oven door partially opened) 1 minute or until top of omelet is lightly browned.
Immediately transfer omelet to a serving platter.
Spread cream cheese mixture evenly over omelet; sprinkle with green onions and ham.
Roll up omelet, jellyroll fashion.
Spoon Cheese Sauce over rolled omelet; sprinkle with bacon.
Serve immediately.