MIX coating mix and cheese on a large plate.
DIP each scaloppine into egg, then coating mixture; place on lightly greased baking sheet.
BAKE at 400°F for 10 - 12 minutes. Meanwhile, prepare sauce: heat dressing in small pan; add tomatoes and onion. Bring to boil; reduce heat and simmer 3 minutes. Spoon over scaloppine.
SERVE over hot cooked fettuccine.
