1. Bring a large pot of salted water to a boil. Add rotini pasta and cook 1 minute less than package instructions. Drain and set aside, reserving 1/4 cup pasta water.

2. In a large skillet, heat olive oil over medium heat. Add chopped onion and cook until soft, about 2–3 minutes.

3. Add ground beef to the skillet, breaking it apart with a spoon. Cook until browned, about 6–8 minutes. Drain excess fat.

4. Add minced garlic and cook for 1 minute until fragrant.

5. Season the beef with Cajun seasoning, smoked paprika, salt, and pepper. Stir to coat evenly. Lower heat.

6. In a small saucepan or microwave-safe bowl, combine Velveeta, heavy cream, and milk. Heat on medium-low, stirring until melted and smooth.

7. Pour the cheese sauce over the beef mixture. Stir well.

8. Add drained pasta to the skillet and toss to combine. Add a splash of reserved pasta water if needed.

9. Remove from heat. Top with grated Parmesan, parsley or herbs, and red pepper flakes if using. Serve warm.