In a large, deep frying pan, melt the 2 tablespoons of unsalted butter over medium heat. This is a crucial step; you want that butter to go bubbly! Once it’s melted, throw in your minced garlic. Sauté it gently, stirring for about 1-2 minutes, until it’s fragrant and just starting to turn golden. Keep an eye on it; burnt garlic is not our friend.

Next up, carefully sprinkle in the heaped tablespoon of flour. Use a whisk to blend this into the garlic and butter. You’re forming a roux which will thicken the sauce. Whisk for another minute to cook that floury taste out; this is all about building flavor.

Now, it’s time to turn our roux into something creamy! Gradually whisk in 1-1½ cups of milk, making sure there are no lumps in sight (because nobody enjoys a lumpy sauce). Keep simmering—just lower the heat a bit—until the mixture thickens, which should take about 5 minutes. If you’re using it, add the ½ cup of heavy cream at this point for an extra luxurious touch.

Having achieved a delightful creamy base, turn off the heat and fold in 2 cups of shredded cheese along with a generous pinch of salt and pepper. Stir until the cheese melts completely, creating that dreamy, cheesy sauce. Don’t forget to add the chopped parsley and the fresh lemon juice—these elevate this dish, making it sing.

Gently add your cooked pasta into the pan with the sauce, and stir it all together. If the sauce looks a bit thick, don’t fret! Toss in a splash of that reserved pasta water a little at a time until you reach your preferred consistency. You want that sauce to cling to your pasta like a best friend.

Transfer the cheesy goodness to your favorite serving dish and maybe sprinkle a bit more parsley or cheese on top for visual appeal. Dig in right away while it’s warm and gooey!