Place veal, butter, mushrooms, onions, rosemary, salt and pepper in 2-quart casserole; cover.
Microwave at medium high (7) 16 to 20 minutes.
Combine cornstarch and water; stir until smooth.
Add to veal mixture.
Microwave at high (10) 2 to 4 minutes until thickened; stir after 1 minute.
Add tomatoes and parsley and Microwave at high (10) 1 to 2 minutes until hot.