Cost information for the following is not included. Normally this is because the quantity or ingredient is unknown
4 tablespoons (1⁄2 stick) unsalted butter
1⁄4 cup AP flour
1 1⁄2 cups low-fat (2%) milk
6 cups thinly sliced rainbow Swiss chard leaves
2 tablespoons sherry wine vinegar
8 lasagna noodles, cooked (according to directions on package)
White truffle oil/spray (optional) for drizzling on top while lasagna is resting