Set a large pot of water on the stove over high heat. Add a tablespoon of salt. Bring to a boil.
While the water heats, chop the sausage into evenly sized pieces. Then, mince the garlic.
Set a large pan over medium high heat. Saute the sausage until nice and crispy on the edges. Remove from heat. Set the sausage aside, leaving about a tablespoon of grease in the pan.
Once the water comes to a rolling boil, cook the pasta according to package directions.
Add the butter to the pan. Saute the garlic until fragrant. Then, add the flour to the pan. Whisk together until smooth. Then add the milk and whisk again.
Add the cheese and stir until fully incorporated. Then, add the sausage back to the pan and stir to incorporate.
As the pasta finishes cooking, remove 2 cups of pasta water, and set to the side. Drain the noodles, and add them to the sauce. Continue to stir and add pasta water bit by bit to reach desired consistency.
