Cook pasta according to package directions. Drain and set aside.
While the pasta is cooking, heat the butter in a saucepan over medium heat until it begins to foam, then whisk in flour until smooth and cook 2 to 3 minutes. Whisk in the milk and seasoning mix and cook, stirring, until thickened, about 5 minutes.
Remove from heat, stir in the cheese until melted, then add the cooked pasta, mixing thoroughly. Serve hot.
For safe meat preparation, reference the USDA website.