Instructions

• Bring a large pot of salted water to a boil. Cook the penne until al dente according to the package directions, then reserve 1/2 cup pasta water and drain.
• Melt the butter in a large skillet over medium heat. Add the garlic and cook for about 30 seconds, just until fragrant and not browned.
• Whisk in the flour and cook for 1 minute to remove the raw flour taste.
• Gradually whisk in the milk until smooth. Cook, whisking often, until the sauce thickens enough to coat a spoon, about 4 to 6 minutes.
• Reduce the heat to low. Stir in the Parmesan, salt, and pepper until the cheese melts and the sauce is smooth.
• Add the drained penne and toss until every piece is coated. Loosen with reserved pasta water, a tablespoon at a time, if needed.
• Taste, adjust the seasoning, and finish with parsley if using. Serve immediately while the sauce is glossy.