Bring a large pot of salted water to a boil and cook the bowtie pasta until al dente according to the package directions. Drain and set aside.
Heat olive oil in a large skillet over medium-high heat. Add the sliced sausage and cook for 4–5 minutes until nicely browned. Remove to a plate.
In the same skillet, melt the butter and sauté the minced garlic for about 30 seconds until fragrant.
Lower the heat to medium. Stir in the heavy cream and milk, then whisk until smooth.
Add the Parmesan cheese a little at a time, stirring constantly until the sauce becomes smooth and creamy.
Mix in the Cajun seasoning, paprika, black pepper, and adjust the salt if needed.
Return the cooked sausage to the skillet and stir to coat it in the sauce.
Add the cooked bowtie pasta and gently toss until every piece is evenly coated.
If the sauce becomes too thick, stir in a few tablespoons of reserved pasta water until you reach the desired consistency.
Sprinkle with fresh parsley and serve immediately while hot.