Description
The BEST Green Bean Casserole Recipe features fresh green beans, homemade creamy mushroom sauce, and golden crispy fried onions. This is not your typical canned soup casserole—every component is made from scratch for incredible flavor and perfect texture. Make-ahead friendly and guaranteed to be the star of your holiday table. Crispy-tender beans in rich, velvety sauce topped with crunchy onions that everyone will love.
Ingredients
FOR THE GREEN BEANS:
2 pounds fresh green beans, trimmed
2 tablespoons salt (for blanching water)
Ice water bath
FOR THE MUSHROOM SAUCE:
3 tablespoons unsalted butter
1 pound cremini mushrooms, sliced thin
3 cloves garlic, minced
1/4 cup all-purpose flour
2 cups whole milk
1 cup heavy cream
1 cup chicken broth or vegetable broth
1 teaspoon soy sauce
1 teaspoon fresh thyme leaves
1/2 teaspoon onion powder
1/2 teaspoon black pepper
1 teaspoon sea salt
Pinch of nutmeg
FOR THE CRISPY ONION TOPPING:
2 large yellow onions, sliced paper-thin
1 cup all-purpose flour
1 teaspoon garlic powder
1 teaspoon paprika
1/2 teaspoon cayenne pepper (optional)
Salt to taste
Vegetable oil for frying (about 2 cups)
OPTIONAL ADD-INS:
1 cup shredded sharp cheddar cheese
1/2 cup grated Parmesan cheese
2 tablespoons fresh parsley, chopped
Instructions
1. Fill a large pot with 4 quarts water, add 2 tablespoons salt, and bring to a rolling boil over high heat.
2. Prepare ice bath in a large bowl with ice and cold water.
3. Drop trimmed green beans into boiling water and blanch for 4-5 minutes until bright green and crisp-tender.
4. Immediately transfer beans to ice bath using a spider strainer, let chill for 3-4 minutes until completely cold.
5. Drain beans thoroughly and spread on clean kitchen towels, pat completely dry.
6. Melt 3 tablespoons butter in a large skillet over medium-high heat until foaming.
7. Add sliced mushrooms in a single layer, sauté 8-10 minutes without stirring for first 4 minutes to allow caramelization.
8. Stir mushrooms occasionally until golden brown and liquid has evaporated.
9. Add minced garlic and sauté for 1 minute until fragrant.
10. Sprinkle 1/4 cup flour over mushrooms, stir constantly for 2 minutes to create a roux.
11. Gradually whisk in milk, then cream, then broth, adding slowly while whisking constantly to prevent lumps.
12. Add soy sauce, thyme, onion powder, pepper, salt, and nutmeg to the sauce.
13. Simmer sauce 5-7 minutes until thickened to consistency of heavy cream, stirring frequently.
14. For crispy onions: Slice onions paper-thin, separate into rings, and place in large bowl.
15. Combine flour, garlic powder, paprika, cayenne, and salt in another bowl.
16. Toss onion rings in flour mixture until evenly coated, shake off excess.
17. Heat vegetable oil in deep skillet to 350°F.
18. Fry onions in small batches for 2-3 minutes until deep golden brown.
19. Remove fried onions with slotted spoon to paper towel-lined plate, season immediately with salt.
20. Preheat oven to 375°F and butter a 9×13-inch baking dish.
21. Combine blanched beans and mushroom sauce in large bowl, toss gently to coat.
22. Transfer mixture to prepared baking dish, spread evenly.
23. Top with half of the crispy fried onions (reserve half for later).
24. Bake uncovered for 25-30 minutes until sauce is bubbling around edges.
25. Add remaining crispy onions in the last 5 minutes of baking.
26. Remove from oven when sauce is bubbling vigorously and edges are lightly golden.
27. Let rest for 5 minutes before serving.
Notes
Casserole can be assembled (without final onion topping) up to 24 hours ahead and refrigerated. Let sit at room temperature 20 minutes before baking.
Fresh green beans are highly recommended over frozen for best texture.
If using frozen beans, thaw completely and pat very dry, skip the blanching step.
Make extra crispy onions—they’re addictive and people will want more!
Store leftover crispy onions separately in airtight container at room temperature to maintain crunch.
For gluten-free version: substitute gluten-free flour 1:1 in both sauce and onion coating.
For dairy-free: use coconut cream instead of heavy cream and dairy milk.
Mushroom sauce should be thick enough to coat the back of a spoon before mixing with beans.
Don’t skip drying the beans thoroughly after blanching—excess water makes casserole watery.
Leftover casserole keeps 3-4 days refrigerated. Reheat covered at 350°F for 15-20 minutes.
Can freeze assembled unbaked casserole up to 1 month. Thaw overnight in refrigerator before baking.
- Prep Time: 20 mins
- Cook Time: 35 mins
- Category: Side Dish
- Method: Baking
- Cuisine: American
Nutrition
- Serving Size: 1 cup
- Calories: 220
- Sugar: 3g
- Sodium: 450mg
- Fat: 15g
- Saturated Fat: 8g
- Unsaturated Fat: 7g
- Trans Fat: 0g
- Carbohydrates: 18g
- Fiber: 3g
- Protein: 6g
- Cholesterol: 45mg
Keywords: green bean casserole, holiday side, mushroom sauce