Stuff We Need
- 3 slices soft white bread, torn into chunks
- 2½ tbsp unsalted butter, room temp
- ¼ tsp fine sea salt
- A pinch (about 1/8 tsp) finely ground black pepper
- 3¼ cups crispy fried onions from a can (about 6.25 oz)
Beans and Sauce
- Salt, for boiling
- 2 lbs fresh green beans, trimmed and cut in half
- 2 tbsp plus 2 tsp unsalted butter
- 1 lb white mushrooms, cleaned and chopped into ½-inch pieces
- 1 tbsp garlic (about 3 large cloves), finely minced
- Black pepper, to taste
- 2 tbsp plus 2 tsp all-purpose flour
- 1½ cups reduced-sodium chicken stock
- 1⅓ cups heavy whipping cream
Stuff to Know Before Cooking
You can prep the casserole in advance. Keep the bread crumb topping in a sealed container in the fridge, and mix in the crispy onions right before baking.
The beans and cooled mushroom sauce can be combined in the baking dish, wrapped tightly in plastic, and chilled for up to 24 hours. When ready to bake, discard the plastic, warm in a 425°F oven for 10 minutes, then top and finish baking.
To halve the recipe, use a 2-quart (or 8-inch-square) baking dish. Cook the sauce until reduced to about 1¾ cups (roughly 6 minutes) and bake for just 10 minutes in the final step.
Make the Topping
Pulse the bread, softened butter, sea salt, and pepper in a food processor until coarse crumbs form (about ten 1-second pulses).
Move to a large bowl, toss with the fried onions, and set aside.
Prep the Oven and Green Beans
Set oven rack to the middle and preheat to 425°F.
Fill a large bowl with water. Boil 4 quarts of water in a Dutch oven. Add 2 tablespoons of salt and the green beans.
Boil until the beans are bright green and just tender, about 6 minutes.
Drain and immediately transfer to the ice water to stop cooking.
Spread beans on paper towels to dry.
Make the Mushroom Cream Sauce
In the now-empty Dutch oven, melt the butter over medium-high heat. Add mushrooms, garlic, ¾ tsp fine salt, and ⅛ tsp ground black pepper.
Cook until mushrooms release liquid and it fully evaporates, about 6 minutes.
Stir in the flour and cook, stirring constantly, for 1 minute. Slowly add in the broth while stirring. Bring to a simmer.
Add the cream, reduce heat to medium, and simmer until reduced to about 3½ cups and thickened, about 12 minutes.
Taste and adjust seasoning with salt and pepper.
Assemble and Bake
Stir the green beans into the sauce to coat evenly. Pour into a 3-quart (13×9) baking dish and smooth the top.
Sprinkle evenly with the topping. Bake until the top is golden and sauce is bubbling at the edges, about 15 minutes.
Serve hot.
Classic Green Bean Casserole
Ingredients
Topping
- 4 slices white sandwich bread each slice torn into quarters
- 2 tbsp unsalted butter softened
- ¼ tsp table salt
- ⅛ tsp ground black pepper
- 3 cups canned fried onions about 6 ounces
Beans and Sauce
- Table salt TT
- 2 lbs green beans ends trimmed, and halved
- 3 tbsp unsalted butter
- 1 lb white button mushrooms stems trimmed, wiped clean, and broken into 1/2-inch pieces (see illustrations below)
- 3 whole medium cloves garlic minced or pressed through garlic press (about 1 tablespoon)
- Ground black pepper TT
- 3 tbsp unbleached all-purpose flour
- 1 ½ cups low-sodium chicken broth
- 1 ½ cups heavy cream
Instructions
- For the Topping: 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, toss with the onions, and set aside.
- For the Beans and Sauce: Adjust the oven rack to the middle position and heat the oven to 425 degrees. Fill a large bowl with ice water. Bring 4 quarts of water to a boil in a large Dutch oven, then add 2 tablespoons of salt and the green beans. Cook until bright green and crisp-tender, about 6 minutes. Drain and immediately plunge the beans into the ice water to stop cooking. Spread them on a paper towel-lined baking sheet to drain.
- In the now-empty Dutch oven, melt the butter over medium-high heat until foaming subsides. Add the mushrooms, garlic, 3/4 teaspoon salt, and 1/8 teaspoon pepper. Cook until the mushrooms release their moisture and the liquid evaporates, about 6 minutes. Stir in the flour and cook for 1 minute, stirring constantly. Gradually stir in the broth and bring to a simmer, continuing to stir. Add the cream, reduce the heat to medium, and let the sauce simmer until thickened and reduced to about 3 1/2 cups, about 12 minutes. Season with salt and pepper to taste.
- Stir the green beans into the sauce until evenly coated. Transfer to a 3-quart (or 13-by-9-inch) baking dish and spread into an even layer. 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.
