Ingredients

• 3 cups milk
• Bay leaf
• 4 tablespoons unsalted butter
• 1/4 cup flour
• 1/4 teaspoon Dijon mustard
• Freshly grated nutmeg
• Salt and pepper
• 1 cup grated white cheddar
• 1 1/2 cups chopped green beans, cut in 2-inch pieces, blanched
• 3 cups sliced assorted wild mushrooms (such as portobello, shiitake, or cremini)
• 1/2 cup freshly grated Parmesan
• 1/2 cup buttered bread crumbs

Instructions

1. Make sauce: In a saucepan scald milk and bay leaf. In another saucepan, melt butter over medium heat. Add flour and cook, whisking constantly, 2 minutes.
2. Remove bay leaf from milk and slowly pour into butter-flour mixture, whisking constantly. Season, to taste, with mustard, nutmeg, salt and pepper. Cook, stirring occasionally, until thickened, about 5 minutes. Remove from heat and add cheddar, stirring until melted and smooth.
3. Heat oven to 350 degrees F. Fold green beans and mushrooms into sauce, then transfer to a buttered casserole. Sprinkle top with Parmesan and buttered bread crumbs. Bake 50 minutes, or until casserole is bubbly and topping is lightly browned.