GREEN BEAN CASSEROLE

Steps:

• 1. FOR THE TOPPING: 1. Pulse the bread, butter, salt, and pepper in a food processor until the mixture resembles coarse crumbs, about ten 1-second pulses. Transfer to a large bowl and toss with the onions, set aside. 2. FOR THE BEANS AND SAUCE Adjust an oven rack to the middle position and heat oven to 425 degrees. Fill a large bowl with ice water. Bring 4 quarts of water to a boil in a large Dutch oven. Add 2 T salt and the beans. Cook until bright green and crisp-tender, about 6 minutes. Drain the beans in a colander and plunge immediately into the ice water to stop the cooking. Spread the beans on a paper towel-lined baking sheet to drain. 3. Add the butter to the now empty Dutch oven and melt over medium-high heat until the foaming subsides. Add the mushrooms, garlic,3/4 t salt, and 1/8 t pepper; cook until the mushrooms release their moisture and the liquid evaporates, about 6 minutes. Add the flour and cook for 1 minute, stirring constantly. Stir in the broth and bring to a simmer, stirring constantly. Add the cream, reduce the heat to medium, and simmer until the sauce is thickened and reduced to 3 1/2 cups, about 12 minutes (it took a little longer to get done). Season with salt and pepper to taste. 4. Add the beans to the sauce and stir until evenly coated. Arrange in an even layer in a 3-quart (or 13 by 9 inch) baking dish. Sprinkle with the topping and bake until the top is golden brown and the sauce is bubbling around the edges about 15 minutes. Serve immediately. What You can do ahead of time. Store the bread crumb topping in an airtight container in the refrigerator for up to 3 days and cobine with the onions just before cooking. Combine the beans and cooled sauce in a baking dish, cover tightly with plastic wrap and refrigerate for up to 24 hours. To serve, remove the plastic wrap and heat the casserole in a 425 degree oven for 10 minutes. Then add the topping and bake as directed.