Step 1: Cook the Pasta
Bring a large pot of salted water to a boil. Cook the rotini pasta according to package instructions until al dente. Drain and set aside.
Step 2: Cook the Beef
In a large skillet, cook the ground beef, onion, and garlic over medium heat until the beef is browned and the onion is softened, about 5-7 minutes. Drain any excess fat. Season with salt, black pepper, and Italian seasoning.
Step 3: Make the Garlic Parmesan Sauce
In the same skillet, melt the butter over medium heat. Add the minced garlic and cook for 1 minute until fragrant. Whisk in the flour and cook for another 1-2 minutes. Gradually pour in the milk, whisking constantly to avoid lumps. Bring to a simmer and cook until the sauce thickens, about 3-4 minutes. Stir in the Parmesan cheese, garlic powder, and onion powder. Season with salt and pepper to taste.
Step 4: Combine and Serve
Add the cooked pasta and beef to the skillet with the sauce. Toss everything together until well coated. Garnish with fresh parsley and serve hot.