Begin by bringing a large pot of salted water to a rolling boil over high heat. Once boiling, add the bowtie pasta and cook until al dente, about 8–10 minutes. Drain the pasta, reserving ½ cup of the pasta water for later use.

In a large skillet, heat 1 tablespoon of olive oil over medium heat. Add the ground beef and cook, breaking it up with a spatula, until browned and fully cooked—about 5–7 minutes. Drain any excess fat.

Push the cooked ground beef to one side of the skillet and melt 2 tablespoons of butter in the open space. Add the chopped yellow onion and sauté for about 3–4 minutes until translucent. Stir in minced garlic and cook for an additional 30 seconds.

Pour in beef broth, scraping any browned bits from the skillet to enhance flavor. Let the mixture simmer for 2–3 minutes, allowing it to reduce slightly.

Reduce the heat to low and gently pour in heavy cream, stirring to combine with the beef and broth mixture. Gradually sprinkle in Parmesan cheese, stirring until the sauce is smooth and thickened.

Add the cooked bowtie pasta to the skillet and toss until it's evenly coated in the creamy sauce. Add reserved pasta water if the sauce is too thick.

Season with salt and black pepper to taste. Garnish with chopped fresh parsley if desired. Serve hot.