About 30 minutes before serving: Preheat oven to 425°F.
In skillet, combine chuck, onion, seasoned salt and pepper; saute 5 minutes or until chuck is brown.
On pastry board, with lightly floured rolling pin, roll 2 of the biscuits, slightly overlapping, into 6" by 5" oval.
On half of oval, pile 3 tablespoons chuck mixture; top with half slice of cheese.
Fold other half of biscuit over cheese; moisten edges with water; pinch together to seal.
Prick top of turnover with fork; lay on ungreased cookie sheet.
Repeat with rest of biscuits.
Bake turnovers 8 to 10 minutes or until brown.