Ingredients
Green Beans
- 2 pounds fresh green beans (washed and trimmed)
Fried Onions
- 1 extra large onion (sliced into thin half-moon slices)
- 1/2 cup flour
- 1 teaspoon kosher salt
- 1 cup milk
- vegetable oil for frying
Cream of Mushroom Soup
- 6 tablespoons butter (divided)
- 1/4 cup diced onion
- 2 cloves garlic (minced)
- 1 pound mushrooms (cremini, white, or mix, cleaned and sliced)
- 1/2 cup white wine (Chardonnay recommended)
- 1/4 cup all-purpose flour
- 3 cups low-sodium chicken broth
- 1 cup heavy cream
- 1 tablespoon soy sauce
- 1/2 teaspoon fresh thyme
- salt and pepper to taste
Instructions
- Preheat Oven: Preheat your oven to 350℉ (175℃) to prepare for baking the casserole later.
- Prepare Fried Onions: Place the onion slices in a plastic baggie and add flour and kosher salt. Shake to lightly coat the onions with flour, then dip them into milk. Return to the baggie and shake again to coat with flour. Fry the onions in hot vegetable oil in small batches until golden brown and crispy. Drain on paper towels and set aside.
- Make Mushroom Soup Base: In a large sauté pan, melt 2 tablespoons of butter over medium-low heat. Add diced onion and cook until softened, about 3-5 minutes. Add minced garlic and cook for about one minute more until fragrant.
- Cook Mushrooms: Add the sliced mushrooms to the pan and cook over medium heat for 8-10 minutes until the liquid evaporates and mushrooms are tender. Season with 1/2 teaspoon kosher salt and freshly ground pepper. Deglaze the pan with white wine, scraping up any browned bits. Let the wine reduce until absorbed by the mushrooms. Remove mushrooms from the pan and set aside.
- Make the Cream Sauce: In the same pan, melt the remaining 4 tablespoons of butter. Sprinkle in 1/4 cup flour and stir continuously for about two minutes to form a roux. Gradually whisk in the chicken broth and heavy cream, cooking until the mixture begins to simmer and thickens into a creamy gravy.
- Combine Soup and Mushrooms: Return the cooked mushrooms and any juices back to the pan. Stir in soy sauce and fresh thyme. Taste and adjust seasoning with salt and pepper. The soup should be flavorful enough to season the green beans.
- Prepare Green Beans: Bring a large pot of water to a boil and blanch the green beans for about 5 minutes until tender but crisp. Immediately transfer the beans to an ice water bath to stop cooking and preserve their vibrant color.
- Assemble Casserole: In a 9×13 inch casserole dish, combine the blanched green beans, the cream of mushroom soup mixture, and half of the fried onions. Cover the dish with aluminum foil.
- Bake: Bake the covered casserole at 350℉ for 20-30 minutes until heated through and edges are bubbly.
- Top and Finish Baking: Remove the foil, sprinkle the remaining fried onions on top, and bake for an additional 5 minutes until the onions are warmed and slightly crisp on top.
Notes
- You can make the mushroom soup base up to three days in advance. Store it covered in the refrigerator and reheat gently before assembling the casserole.
- Use fresh green beans for the best texture and flavor but frozen can be used if fresh is unavailable (adjust blanching times accordingly).
- For a vegetarian version, substitute vegetable broth for chicken broth and use a vegetarian Worcestershire or omit the soy sauce if preferred.
- Make sure not to overcrowd the onions when frying to ensure they become crispy instead of soggy.
- Let the casserole rest a few minutes after baking to allow it to set before serving.
- Prep Time: 25 minutes
- Cook Time: 1 hour 5 minutes
- Category: Side Dish
- Method: Baking
- Cuisine: American
