Slice the andouille sausage into 1/8 inch rounds
Heat a skillet to medium hot - water drops should sizzle. Place a single layer of sausage into the skillet and cook for 2-3 minutes - until they have a nice color (brown not charred). Flip and do the same on the other side. remove onto a paper towel lined dish. Leave the oil in the skillet. You will need to cook the sausage in batches.
While the sausage is cooking, dice the onion and celery
Once the sausage is done, lower the heat to medium and sauté the onion for 2-3 minutes until it starts to soften
Add the celery and cook until onions are translucent and celery is softened
Add the Angel Dust seasoning and coat the veggies
Add the chicken stock and bring to a boil
Reduce heat to low/simmer and stir in the heavy cream
Add the sausage back into the skillet. The liquid should just cover the sausage
Simmer covered for about 5 minutes and then taste the sauce. Add salt and pepper (or additional Angel Dust) to taste.
Simmer partially covered on low for about 30 minutes so it can reduce. Stir occasionally
While the sausage is simmering, bring a large pot of well salted water to a boil.
Once you have a rolling boil, add the rigatoni (cook to instructions on the package)
While the pasta is cooking, put the flour and 1 tbsp of cold water in a small cup and mix thoroughly into a slurry. You will use the flour slurry to thicken the sauce. Stir it into the sauce and mix well. The sauce should thicken enough to coat the back of a spoon.
Drain the pasta and return it to the pot. Add the sauce and sausage and mix gently but thoroughly.
Serve immediately
I find that this dish doesn't really need any cheese. But you can grate fresh parmesan over the plate if you wish.