Spinach Mac and Cheese
Spinach Mac and Cheese 3 tablespoons unsalted butter 1/2 cup minced yellow onion 1/3 cup all-purpose flour 4 cups whole milk, room temperature Coarse salt and ground pepper 2 bunches curly- or flat-leaf spinach (about 1 3/4 pounds total), trimmed, washed, and cut crosswise into 1/2-inch-thick strips 5 ounces Gruyere cheese, grated (2 cups) 3/4 […]