Description

This classic Green Bean Casserole features tender green beans coated in a creamy mushroom sauce and topped with crispy, golden fried onions. Boiled green beans are smothered in a savory, thick mushroom and cream sauce, then baked with crunchy homemade onion topping for a perfect balance of textures and flavors. Ideal as a comforting side dish for holidays and family dinners.

Ingredients

Scale

Green Beans

750g / 1.5lb green beans, trimmed and halved

Crispy Onions

2 large yellow onions, peeled, halved and thinly sliced (or 3 medium)
1/4 cup (35g) plain/all-purpose flour
2 tbsp panko breadcrumbs
1/2 tsp salt
1/4 tsp black pepper
4 cups / 1 litre vegetable oil (or peanut, canola oil) for deep-frying

Creamy Mushroom Sauce

3 tbsp (50g) unsalted butter
360g / 12 oz mushrooms, chopped into 1cm / 1/3″ pieces
3/4 tsp salt
1/4 tsp black pepper
2 garlic cloves, minced
3 tbsp (35g) plain/all-purpose flour
1 1/2 cups (375ml) low sodium vegetable or chicken broth/stock
1/2 cup (125ml) heavy/thickened cream
Pinch of nutmeg or freshly grated nutmeg

Instructions

Prepare the Green Beans: Boil the trimmed and halved green beans in water for 3 minutes or until just tender. Drain and immediately rinse under cold tap water to stop the cooking process. You can also opt to steam the beans. Transfer to a clean tea towel and pat dry. Set aside.
Make the Crispy Onions: Line a tray with 3-4 layers of paper towels. Toss the sliced onions with flour, panko breadcrumbs, salt, and pepper until well coated. Heat about 2cm (3/4″) of vegetable oil in a heavy-based skillet over medium-high heat. Test the oil by dipping the end of an onion slice; it should sizzle immediately. Fry onions in batches, making sure not to overcrowd the pan, for about 1 1/2 minutes or until they turn light golden brown. Remove onions with a slotted spoon and spread them out on the paper towel-lined tray to cool. Do not cover.
Prepare the Creamy Mushroom Sauce: In a skillet over medium-high heat, melt unsalted butter. Add chopped mushrooms and cook for 1 minute. Season with salt and pepper and cook until mushrooms begin to soften, approximately 1.5 minutes. Add minced garlic and cook for another minute until garlic is golden. Reduce heat to medium and sprinkle in flour, stirring continuously until the flour is fully absorbed. Gradually pour in half of the broth while stirring to dissolve any lumps. Then add the remaining broth and the cream, stirring well. Add a pinch of nutmeg and stir again. Cook the sauce for 5 minutes, stirring occasionally at first, then more regularly as it thickens, until it coats the back of a wooden spoon and leaves a trail when a line is drawn through with your finger.
Assemble and Bake the Casserole: Preheat your oven to 350°F (180°C, 160°C fan). Place the cooked green beans into the pot you used for boiling or a mixing bowl. Pour the mushroom sauce over the beans and stir to combine. Transfer the mixture into a 2.5-quart / 2.5-liter casserole dish, smoothing the surface. Evenly sprinkle the crispy fried onions on top, reserving any leftovers. Bake in the preheated oven for 15 minutes until the edges bubble and the onions turn deep golden brown. Check at 10 minutes to ensure the onions do not burn. Serve immediately.

Notes

Note 1: Panko breadcrumbs provide extra crunch to the onion topping but other breadcrumbs can be substituted if unavailable.
Note 2: Vegetable oil is preferred for frying due to a neutral flavor, but peanut or canola oil works as alternatives.
Note 3: Do not pile the fried onions on the tray to prevent sogginess; spacing helps them stay crispy.
Note 4: A 2.5-quart/2.5-liter casserole dish works best to evenly cook and brown the dish.
Note 5: Keep an eye on the onions while baking to avoid burning; remove early if necessary.
This casserole can be partially assembled ahead by preparing green beans, mushroom sauce, and frying onions separately then combining just before baking.

Prep Time: 20 minutes
Cook Time: 35 minutes
Category: Side Dish
Method: Baking
Cuisine: American

Keywords: Green bean casserole, creamy mushroom sauce, fried onions, classic side dish, holiday recipe