Melt 6 tablespoons of butter in a large saucepan over medium heat until bubbling gently.
Add minced garlic and sauté for 1-2 minutes until fragrant, avoiding burning.
Sprinkle in 6 tablespoons of flour, stirring continuously to form a roux, cooking for 1-2 minutes.
Gradually whisk in 3 cups of chicken broth, stirring until thickened, about 5-7 minutes.
Reduce heat to low, add 1 cup of heavy cream, 1 tablespoon of Italian seasoning, and 1 teaspoon of onion powder, mixing well.
Add 1 ½ cups of grated Parmesan cheese, stirring until melted and smooth. Season with salt and pepper to taste.
Remove from heat and serve warm over pasta, grilled chicken, or vegetables.