Beechers Flagship Cheese Sauce

Name: Beecher's Flagship Cheese Sauce
Ingredients: ½ stick (4 tablespoons) unsalted butter; ⅓ cup unbleached all-purpose flour; 3 cups milk; 14 ounces cheddar cheese, preferably Flagship, grated (about 3 ½ cups); 2 ounces Jack cheese, preferably Just Jack, grated (about ½ cup); ½ teaspoon kosher salt; 1/4 to 1/2 teaspoon chipotle-chile powder; ⅛ teaspoon garlic powder