Bring a large pot of salted water to a rolling boil. Add the bowtie pasta and cook according to package directions until al dente. Reserve 1 cup of the pasta cooking water, then drain the pasta and set aside.

While the pasta cooks, heat olive oil in a large skillet or Dutch oven over medium-high heat. Add the ground beef, season with salt and pepper, and cook, breaking it up with a spoon, until browned and no pink remains, about 6-8 minutes. Drain excess grease, leaving about 1 tablespoon.

Reduce heat to medium. Add butter and diced onion to the skillet. Cook until softened, about 3 minutes. Add minced garlic, Italian seasoning, smoked paprika, and red pepper flakes. Sauté for 1 minute until fragrant.

Pour in beef broth and Worcestershire sauce. Scrape up any browned bits. Simmer for 3 minutes to reduce slightly.

Reduce heat to low. Stir in heavy cream gently to prevent splitting, heating until warm but not boiling.

Remove from heat or keep very low. Stir in grated Parmesan until melted and smooth. Add reserved pasta water if needed to reach desired consistency.

Add drained pasta to the skillet. Toss to coat. Garnish with parsley and extra Parmesan. Serve immediately.