Preheat your oven to 425°F.
In a large pot, bring water to a rolling boil, add a tablespoon of salt, and cook the macaroni until al dente, then drain.
In a skillet, fry the bacon until golden and set aside on paper towels, keeping the grease in the pan.
Combine remaining butter with bacon grease, then whisk in flour and cook until golden brown.
Gradually pour milk and cream into the roux, bring to a simmer, and season with salt, pepper, and red pepper flakes.
Save some cheese for topping, and whisk the rest into the sauce until smooth.
Toss the drained macaroni with the cheese sauce and half of the bacon.
Grease a baking dish with butter, transfer the mac and cheese into it, and sprinkle with the reserved cheese and bacon.
Cook in the preheated oven until bubbly and golden on top.
Serve the bacon mac and cheese hot from the oven.