Creamed Spinach And Leeks With Cheddar recipes

Name: Creamed Spinach And Leeks With Cheddar recipes
Ingredients: kosher salt; 1 pound spinach leaves; 4 tablespoons unsalted butter, preferably European-style; 2 tablespoons neutral-flavored olive oil; 2 large leeks, including some of the green, halved lengthwise and sliced crosswise; 3/4 teaspoon dry mustard; 3/4 teaspoon plus a large pinch freshly ground white pepper; 2 tablespoons Apple butter, store-bought; 1 tablespoon plus 1 1/2 teaspoons unbleached all purpose flour; 1 3/4 cups whole milk, warm; 1 1/2 cups packed coarsely grated cheddar cheese, preferably Irish