Green Bean Casserole
- 4 Slices (6 ounces) hearty white sandwich bread
- 2 Tablespoons unsalted butter
- 1/4 Teaspoon table salt
- 1/8 Teaspoon ground black pepper
- 3 Cups canned fried onions (about 6 ounces)
- Beans and sauce
- 2 Pounds green beans
- table salt
- ground black pepper
- 3 Tablespoons unsalted butter
- 1 Pound white button mushrooms
- 3 garlic cloves , minced
- 3 Tablespoons all-purpose flour
- 1 1/2 Cups low-sodium chicken broth
- 1 1/2 Cups heavy cream
Soften 2 tablespoons butter on the counter for 30 minutes. Tear 4 slices hearty white sandwich bread into quarters. Pulse bread, softened butter, 1/4 teaspoon table salt, and 1/8 teaspoon pepper in food processor until mixture resembles coarse crumbs, about 10 pulses. Transfer to large bowl, cover, and refrigerate for up to 2 days.
Fill large bowl with ice water. Line rimmed baking sheet with paper towels. Bring 4 quarts water to boil in Dutch oven. Trim ends from 2 pounds green beans. Cut beans in half crosswise. Add beans and 2 tablespoons table salt to boiling water and cook until beans are bright green and crisp-tender, about 6 minutes. Drain beans in colander, then plunge immediately into ice water to stop cooking. Spread beans on prepared baking sheet to drain.
Trim thin slice from bottom of stems on 1 pound white button mushrooms. With hands, break mushrooms into ½-inch pieces. Peel and mince 3 garlic cloves. Melt 3 tablespoons butter in now-empty Dutch oven over medium-high heat. Add mushrooms, garlic, 3/4 teaspoon table salt, and 1/8 teaspoon pepper and cook until mushrooms release moisture and liquid evaporates, about 6 minutes. Add 3 tablespoons all-purpose flour and cook for 1 minute, stirring constantly. Stir in 1 ½ cups low-sodium chicken broth and bring to simmer, stirring constantly. Add 1 ½ cups heavy cream, reduce heat to medium, and simmer until sauce is thickened and reduced to 3 ½ cups, about 12 minutes. Season with salt and pepper to taste.
Add green beans to sauce and stir until evenly coated. Arrange in even layer in 3‑quart (or 13- by 9‑inch) baking dish. Cover with plastic wrap and refrigerate for up to 24 hours.
Adjust oven rack to middle position and heat oven to 425 degrees. Remove plastic wrap and bake green beans for 10 minutes. Toss bread crumb topping with 3 cups (about 6 ounces) canned fried onions. Sprinkle topping over green beans. Continue baking until top is golden brown and sauce is bubbling around edges, about 15 minutes. Serve immediately.