Name: Green Bean Casserole
Prep time: 15 min
Cook time: 1 h
Total time: 1 h 15 min
Cuisine: American
Ingredients: 750g / 1.5 lb green beans, trimmed and halved; Crispy Fried Onions:; 2 large yellow onions, halved and thinly sliced; 1/4 cup (35g) all-purpose flour; 2 tbsp panko breadcrumbs; 1/2 tsp salt; 1/4 tsp black pepper; 4 cups (1 liter) vegetable oil (or peanut/canola oil); Creamy Mushroom Sauce:; 3 tbsp (50g) unsalted butter; 360g / 12 oz mushrooms, chopped into 1cm pieces; 3/4 tsp salt; 1/4 tsp black pepper; 2 garlic cloves, minced; 3 tbsp (35g) all-purpose flour; 1 1/2 cups (375ml) vegetable or chicken broth (low sodium); 1/2 cup (125ml) heavy cream; Pinch of nutmeg (optional)

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This Green Bean Casserole is a holiday classic elevated with a rich, creamy mushroom sauce and crispy homemade fried onions. Every bite delivers perfectly tender green beans, savory sauce, and a golden, crunchy topping that makes this dish unforgettable. Whether you’re hosting Thanksgiving or just craving comfort food, this side dish is a showstopper.

Why You’ll Love This Recipe

This isn’t your average green bean casserole. The from-scratch mushroom sauce is silky and full of depth, and the fresh green beans retain just the right amount of bite. Homemade crispy onions offer a delicate crunch that store-bought versions can’t match. With make-ahead tips included, it’s both impressive and practical.

Green Bean Casserole

Ingredients

(Tip: You’ll find the full list of ingredients and measurements in the recipe card below.)

For the green beans:

750g / 1.5 lb green beans, trimmed and halved

For the crispy fried onions:

2 large yellow onions (or 3 medium), thinly sliced
1/4 cup all-purpose flour
2 tablespoons panko breadcrumbs
1/2 teaspoon salt
1/4 teaspoon black pepper
4 cups vegetable oil, for frying

For the creamy mushroom sauce:

3 tablespoons unsalted butter
360g / 12 oz mushrooms, chopped
3/4 teaspoon salt
1/4 teaspoon black pepper
2 garlic cloves, minced
3 tablespoons all-purpose flour
1 1/2 cups low-sodium vegetable or chicken broth
1/2 cup heavy cream
Pinch of nutmeg

Directions

Prepare the green beans:

Boil green beans for 3 minutes until just tender. Drain and rinse under cold water to stop cooking. Pat dry and set aside.

Make the crispy onions:

Toss sliced onions with flour, panko, salt, and pepper.
Heat about 2cm of oil in a skillet over medium-high heat. Test with one onion slice—it should sizzle immediately.
Fry onions in small batches for about 1 ½ minutes until light golden brown. Transfer to a paper towel–lined tray. Do not cover.

Make the mushroom sauce:

In a skillet, melt butter over medium-high heat. Add mushrooms, salt, and pepper. Cook for 2–3 minutes, then add garlic and cook another minute.
Reduce heat to medium, stir in flour and cook until absorbed.
Slowly add half the broth while stirring, then add remaining broth and cream. Add nutmeg.
Simmer for 5 minutes, stirring until thick enough to coat the back of a spoon.

Assemble and bake:

Preheat oven to 350°F (180°C).
Combine green beans and sauce, then transfer to a 2.5-quart baking dish.
Top with crispy onions and bake for 15 minutes, or until bubbling and golden. Check at 10 minutes—cover with foil if onions are browning too quickly.
Serve immediately.

Servings and timing

This recipe serves 8 to 12, depending on other dishes served.
Prep time: 15 minutes
Cook time: 1 hour
Total time: 1 hour 15 minutes

Variations

Use store-bought onions: For convenience, substitute with packaged French fried onions.
Make it gluten-free: Use gluten-free flour and certified GF panko.
Lighter version: Use half-and-half or milk instead of heavy cream.
Cheesy twist: Add ½ cup shredded gruyère or parmesan to the sauce before baking.

Storage/Reheating

Make ahead:

Cook green beans and prepare sauce up to 3 days ahead. Store separately in the fridge.
Fry onions the day before—store at room temperature in an airtight container.
Assemble and bake on the day, topping with onions just before baking.

Storage:

Refrigerate leftovers in an airtight container for up to 3 days.

Reheating:

Reheat in a 350°F oven, loosely covered with foil to prevent the onions from burning. Uncover during the last few minutes for a crisp top.

FAQs

Can I use canned green beans?

Fresh or frozen green beans are preferred for texture, but canned can be used in a pinch. Drain well and skip boiling.

How do I keep the onions crispy?

Drain them well after frying and don’t cover. Top the casserole just before baking.

Can I use a different vegetable?

Yes. Broccoli, cauliflower, or a medley of vegetables can be used in place of green beans.

What kind of mushrooms work best?

White button or cremini mushrooms work well. A mix of wild mushrooms can elevate the flavor.

Can I make it vegan?

Yes. Use plant-based butter and cream, and vegetable broth. Ensure your onions and panko are also vegan-friendly.

How thick should the sauce be?

Thick enough to coat the back of a spoon—don’t let it over-reduce or it may dry out in the oven.

Can I use milk instead of cream?

Yes, but the sauce will be thinner and less rich. Whole milk works best.

What can I serve this with?

It pairs well with roast meats, stuffing, mashed potatoes, and cranberry sauce for a full holiday meal.

Can I freeze green bean casserole?

It’s best fresh or refrigerated. Freezing may affect texture, especially of the onions.

How do I know when it’s done baking?

The edges should be bubbling, and the onions deep golden. Check at 10 minutes to avoid burning.

Conclusion

This Green Bean Casserole is a comforting classic with an upgrade—rich mushroom sauce, vibrant green beans, and the crispiest onions. Whether it’s for Thanksgiving or just a cozy Sunday dinner, this dish hits all the right notes of creamy, crunchy, and flavorful. With easy make-ahead steps and customizations, it’s a reliable and delicious addition to any meal.