Classic Green Bean Casserole (From Scratch)

A creamy, crunchy comfort food favorite that elevates the humble green bean

Modern kitchen scene with fresh ingredients arranged on marble countertops, wooden utensils, ceramic bowls, with daylight streaming in from a window.

Key Info:

Prep Time: 30 minutes
Cook Time: 30 minutes
Total Time: 60 minutes
Servings: 8-10
Difficulty: Moderate
Dietary: Vegetarian (with vegan/GF options noted)

Equipment Needed:

Large skillet or sauté pan
9×13-inch casserole dish
Large mixing bowl
Whisk
Colander
Alternative: Any oven-safe baking dish

Ingredients:

For the Base:

1.5 lbs fresh green beans, trimmed (or 4 14.5oz cans, drained)
16 oz cremini mushrooms, sliced
1 medium onion, diced
3 cloves garlic, minced

For the Sauce:

4 tbsp (60g) butter [vegan: plant butter]
4 tbsp (60g) all-purpose flour [GF: rice flour]
2 cups (480ml) whole milk [vegan: unsweetened almond milk]
1 cup (240ml) vegetable broth
1 tbsp soy sauce [GF: tamari]
1 tsp fresh thyme
Salt and pepper to taste

Topping:

1.5 cups French-fried onions
½ cup grated Parmesan (optional)

Golden-brown sautéed mushrooms and onions in a large stainless steel skillet in a modern kitchen with green subway tile backsplash, under natural daylight

Method:

1. Preheat oven to 350°F (175°C)

2. If using fresh beans:

Bring large pot of salted water to boil
Blanch beans for 5 minutes until bright green
Immediately plunge into ice water
Drain and set aside

3. Make the sauce:

Melt butter in large skillet over medium heat
Add mushrooms, cook until golden (8-10 minutes)
Add onions, cook until translucent (5 minutes)
Add garlic, cook 1 minute
Stir in flour, cook 2 minutes
Gradually whisk in milk and broth
Simmer until thick enough to coat spoon (5-7 minutes)

Creamy sauce being poured on green beans in a modern kitchen with white marble countertops, wooden utensils, and cream-colored ceramic bowls

4. Combine:

Mix beans with sauce in casserole dish
Top with fried onions and cheese if using

Unbaked casserole with french-fried onions and parmesan in a modern kitchen with white marble countertops, green subway tile backsplash, and stainless steel appliances

5. Bake:

25-30 minutes until bubbling and golden

Crucial Tips:

Don’t overcook the beans – they’ll continue cooking in the oven
Let sauce thicken properly before combining
Add onion topping only in final 10 minutes to prevent burning

Storage:

Refrigerate up to 4 days
Freeze without topping for up to 2 months
Reheat at 350°F until hot

Scaling:

Recipe doubles easily for larger crowds
Use multiple smaller dishes for easier serving

Variations:

Add crispy bacon
Use different mushroom varieties
Top with buttered breadcrumbs
Add water chestnuts for extra crunch

Common Mistakes:

Soggy beans from overcooking
Thin sauce from rushing the roux
Burnt topping from adding too early