01 - In a medium saucepan over medium heat, melt the butter. Add the minced garlic and sauté for 1 minute until fragrant but not browned.
02 - Sprinkle in the flour and whisk continuously for 1 minute to form a smooth roux.
03 - Slowly pour in the heavy cream and milk, whisking constantly to avoid lumps.
04 - Bring the mixture to a gentle simmer, stirring frequently, until it thickens, about 3 to 5 minutes.
05 - Reduce heat to low, then stir in the Parmesan cheese, salt, black pepper, and nutmeg. Continue stirring until the cheese is fully melted and the sauce is silky.
06 - Taste and adjust seasoning as needed. Serve immediately or keep warm on low heat.