Step 1: Cook the pasta in a large pot of salted boiling water according to package directions until al dente. Reserve 1/2 cup of pasta water before draining.
Step 2: While the pasta cooks, heat a large skillet over medium-high heat. Add the sliced sausage and cook until browned on both sides, about 5-7 minutes.
Step 3: Remove the sausage from the skillet and set aside. In the same skillet, add the onions and cook until translucent, then add the garlic and cook for another 1 minute until fragrant.
Step 4: Pour in the heavy cream and smoked paprika. Bring to a gentle simmer, then stir in the Parmesan cheese until melted and smooth.
Step 5: Return the sausage to the skillet and add the cooked pasta. Toss to coat thoroughly, adding reserved pasta water as needed to reach your desired sauce consistency.
Step 6: Season with salt and pepper. Garnish with fresh parsley and serve immediately.