In a large dutch oven over medium-low heat, add the bacon and cook until crispy. Drain the bacon and reserve on the side. Drain off half of the bacon grease and discard. Sautee the garlic in the bacon fat until fragrant, about 1 minute. Add in the rigatoni and coat in the fat. Add the chicken stock and stir to combine. Bring to a boil, reduce to a simmer, cover and simmer for 12 minutes or until the pasta is al dente, stirring every couple minutes to make sure the pasta doesn't stick the bottom of the pan.
Once the pasta is cooked, add in the cream cheese and cheddar, let melt stirring constantly. Add in the ranch, diced chicken, and peas, stir to combine. Let simmer until the sauce is thickened to your liking, about 3-5 minutes.**
Serve with the leftover bacon on top, with an optional garnish of parsley, scallions, and more ranch.
Notes
* I use rotisserie chicken, so easy!**The pasta will continue to soak up the sauce after cooking, keep this in mind while thickening.