OMG, I can't believe I've not posted about this yet. This is by far one of mine and Shea's most favoritist dishes of all time. (and yes I know that's not a word :P)
I was watching Ultimate Recipe Showdown and one of the winners did a similar pasta. Five cheeses bacon mac and cheese. You can get the TGIF modified version on their menu.
Here's the basic proceedure I use.
I boil my pasta as package directions indicate. I use Ziti, Penne or Elbow Macaroni. My kids prefer the latter, my husband one of the former, but all is good.
Cut about 3/4 lb to 1 lb of bacon into bite size bits and fry them in a pan until crispy. Be cafeful with your bacon selection, the wrong one can really ruin the meal. It must say smoked and really shouldn't be low sodium as we don't add any salt to anything other than the pasta water.
When the bacon is crispy take it out of the grease and drain, but don't drain the grease from the pan we need it! I generally use all of the renderings, but that's up to you if you want to and how much liquid you intend to use. I don't measure much these days so I can't tell you how much. A typical roux is 1T of fat, 1T of flour to 1 cup of liquid depending on your consistency you want more or less liquid.
Add flour to the bacon drippings. I generally use three small handfuls of flour. Cook the flour so it's cooked and gets rid of that flour taste. Stir in the milk and/or half and half. I typically use 2% milk but any other than skim should work fine. It's about 1 quart of liquid but again I don't actually measure when I'm doing it.
Add in about 2 cups of grated cheddar cheese into the milk bacon dripping mixture. Stir together until desired consistency.
Drain the pasta and pour the cheese sauce over it.
I generally grill chicken about 3 breasts and then cut it up into small bite size pieces, throw it into the pasta and sauce and add in the bacon, mix well and heat the rest through and blends together nicely.
While this is not a low fat meal it is AWESOME! It makes even better leftovers. And this is coming from someone who does not like leftovers.