Steps:

1. Boil the macaroni with salty water for 8-12 minutes.
2. In a saucepan, melt the butter over medium heat, add the flour and cook for 1 minute. Add the milk in 3 stages constantly whisking to remove any lumps. The milk should thicken like cream.
3. Once the sauce coats the back of a spoon, you should be able to draw a path with your finger. Remove from the heat and add the gruyere and mozzarella, stir until melted.
4. Adjust the seasoning with salt.
5. Drain the pasta and mix with the cheese sauce and Baken Real Bacon Crisps.
6. Place into a baking dish and sprinkle the parmesan cheese over.
7. Set the oven to grill at 220 degree Celsius, and place into the oven for 5-8 minutes until golden brown.