Mix  thoroughly; eggs, cream, seasoning salt, pepper,  and onion powder in a bowl. Melt butter in skillet. Add egg mixture. Cover skillet with glass lid.  Cook on low temperature till eggs  arefluffy and cooked.  Remove lid.  Sprinkle  eggs with cheese,  and add the ham.  Cover  skillet with lid. Let the cheese melt. Remove from heat. Remove lid. Spread sour cream over top of ommellette. Fold ommellette. Cut into 3rds. Serve.    Variations:  Chicken,  or crab can be subtituted for the ham.  Avacado can be added after the sour cream.  This ommellette is good with any toppings you want to put on it. Another variation. Put pizza sauce on flluffy cooked ommellette, and add pepperoni on top of the cheese.  Voila , Pizza Ommellete. It tastes just like pizza without the carbs!