1Heat oven to 350°. Grease square baking dish, 8x8x2 inches.
2Mix baking mix, milk, mustard and egg until blended. Pour half of the batter into baking dish. Top with half of the ham and 1/2 cup of the cheese. Top with remaining ham. Pour remaining batter over ham.
3Bake 45 to 50 minutes or until golden brown and set. Sprinkle with remaining 1/2 cup cheese. Let stand 5 minutes before cutting.