Classic Mac & Cheese

Put a large pot of water on to boil. Cook pasta according to package directions. Drain.

Meanwhile, heat 1 1/2 cups milk in a large heavy saucepan over medium-high heat until steaming. Whisk the remaining 1/4 cup milk and flour in a small bowl until smooth; add to the hot milk and cook, whisking constantly, until the sauce simmers and thickens, 2 to 3 minutes. Add butter and whisk until melted. Remove from heat and stir in Cheddar until melted. Stir in salt and pepper. Add the drained pasta and stir to combine.