Gradually pour in the milk and heavy cream, stirring between additions. Bring the mixture to a boil, then reduce the heat to a light simmer and cook until the sauce begins to thicken.
Season with salt, pepper and Italian seasoning.
Add the Parmesan cheese and stir until melted.
Stir in the cooked penne and reserved pasta water, then toss well to combine.
Notes
Do not rinse the pasta.
Use freshly grated Parmesan for best texture.
Store leftovers in an airtight container in the refrigerator for up to 3 days.
To freeze, cool completely and store in a freezer-safe container for up to 1 to 2 months.
Reheat gently with added milk or broth over low heat to restore creaminess.
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