Bring a large pot of salted water to a rolling boil. Add bowtie pasta and cook according to package instructions until al dente, about 10-12 minutes. Reserve ½ cup of pasta water and then drain the rest.

In a large skillet, melt 1 tablespoon of butter over medium-high heat. Add ground beef with half the Cajun seasoning, salt, and pepper. Sauté for about 7-8 minutes until browned. Remove beef from skillet.

Lower heat to medium and add remaining tablespoon of butter to the skillet. Add minced garlic and sauté for about 30 seconds until fragrant.

Add softened cream cheese to the skillet, stirring until melted. Gradually whisk in milk or half-and-half, stirring until smooth. Add grated Parmesan cheese and remaining Cajun seasoning. Let it simmer for 2-3 minutes until slightly thickened.

Return ground beef to the skillet, add drained bowtie pasta, and toss until coated. Stir in reserved pasta water if the sauce is too thick.

Serve hot, garnished with extra Parmesan cheese and chopped parsley. Add more red pepper flakes if desired.