Place Extra Melt Cheese shreds, bacon and onion in large bowl.
In medium bowl, whisk together eggs, half and half, salt and cayenne pepper. Pour eggs over bacon mixture. Stir until well combined.
Place pie shell on baking tray and pour mixture into pie shell. Bake in 425°F heated oven for 15 minutes. Reduce oven heat to 300°F. Bake for an additional 30 to 40 minutes until knife inserted in center comes out clean.
While quiche is baking, in small saucepan combine Alfredo Sauce and Extra Melt Cheese Sauce. Heat to 165°F. Hold warm.
Allow quiche to rest for 10 minutes before slicing. Serve with 2 ounces Mornay Sauce over top of each slice.