Easy Green Bean Casserole from Scratch
Green bean casserole made from scratch takes about 20 minutes more than the canned-soup version. The fresh green beans stay crisp-tender, and the mushroom sauce tastes of browned mushrooms, garlic and Parmesan instead of salt.
You can assemble it the day before and bake it while the turkey rests, which frees up the oven when Thanksgiving gets busy. The full recipe is in the card below.
Easy Green Bean Casserole from Scratch
Equipment
- Large pot
- Colander
- Large skillet (12-inch)
- Whisk
- 9×13-inch (3-quart) baking dish
- Instant-read thermometer
Ingredients
Green beans
- 2 pounds fresh green beans trimmed and cut into 2-inch pieces
- 2 teaspoons salt for the cooking water
Mushroom sauce
- 3 tablespoons unsalted butter
- 8 ounces cremini mushrooms sliced
- 1 medium shallot finely chopped
- 3 cloves garlic minced
- 3 tablespoons all-purpose flour
- 1 cup low-sodium chicken broth or vegetable broth
- 1 cup whole milk
- ½ cup finely grated Parmesan
- ½ teaspoon salt
- ¼ teaspoon black pepper
Topping
- 1 container crispy fried onions 6 ounces, divided
Instructions
- Heat the oven to 350°F (175°C). Grease a 9×13-inch baking dish.
- Bring a large pot of water to a boil and add 2 teaspoons salt. Add the green beans and cook for 4–5 minutes, until bright green and crisp-tender. Drain, rinse under cold running water until cool, and drain well.
- Melt the butter in a large skillet over medium-high heat. Add the mushrooms and cook for 6–8 minutes, stirring occasionally, until browned and their liquid has cooked off. Add the shallot and garlic and cook for 1–2 minutes, until soft.
- Sprinkle the flour over the mushrooms and stir for 1 minute. Slowly whisk in the broth, then the milk. Simmer for 3–5 minutes, stirring often, until the sauce thickens enough to coat a spoon.
- Remove from the heat and stir in the Parmesan, 1/2 teaspoon salt and the pepper.
- Add the green beans and 1 cup of the fried onions to the skillet and stir to coat. Spread the mixture in the baking dish.
- Bake uncovered for 25 minutes, until bubbling at the edges and the center reaches 165°F (74°C).
- Scatter the remaining fried onions over the top and bake for 5–10 minutes more, until the onions are deep golden. Rest for 5 minutes before serving.
Notes
Why This Green Bean Casserole from Scratch Works
Blanching the green beans first sets their color and cooks them most of the way, so they finish in the oven without turning soft or gray.
Browning the mushrooms properly gives the sauce its depth. Let them sit in the hot pan until their liquid cooks off and the edges turn golden before adding anything else. The flour, broth and milk then turn the pan into a sauce in a few minutes.
Half the fried onions go into the casserole and half on top. The ones inside soften and season the sauce; the ones on top stay crunchy because they go on near the end of baking.
Choosing Green Beans
Look for firm, bright green beans that snap cleanly when bent. Skip any that are limp, wrinkled or have brown spots.
Thin French beans (haricots verts) also work. They cook faster, so blanch them for a minute or two less. Frozen cut green beans are a good backup; thaw and dry them well so the sauce does not turn watery.
Lighter Green Bean Casserole Swaps
The card keeps the sauce lighter than many recipes by using milk instead of heavy cream. To trim it further:
- Use 2% milk instead of whole milk.
- Top with half the fried onions, mixed with 1/2 cup panko breadcrumbs for crunch.
- Add an extra 1/2 pound of green beans without changing the sauce, for more vegetables per serving.
Making Green Bean Casserole Ahead for Thanksgiving
You can assemble the casserole up to a day ahead, cover it and keep it in the refrigerator. Leave the topping off until it goes in the oven, or the onions will lose their crunch.
A dish straight from the fridge needs a longer bake, so check the center with a thermometer before adding the last of the onions.
What to Serve with Green Bean Casserole
Green bean casserole is usually served with roast turkey, and it works just as well on a weeknight. Serve it with our sheet pan chicken dinner or with baked BBQ chicken drumsticks for an easy family dinner.
On a Thanksgiving table, it sits well next to our sweet potato casserole, garlic mashed potatoes, crockpot mac and cheese and homemade cranberry sauce.
For a lighter plate, pair a smaller scoop with garlic butter salmon.
Storage and Reheating
Store leftovers in an airtight container in the refrigerator for up to 4 days. Reheat in a covered baking dish at 350°F, or in the microwave, until hot all the way through (165°F). The topping softens in the fridge; scatter a few fresh fried onions on top after reheating.
Green Bean Casserole FAQ
Can I make green bean casserole without canned soup? Yes. This recipe makes the creamy mushroom sauce from butter, mushrooms, flour, broth and milk in one skillet.
Can I freeze green bean casserole? It is not ideal. The beans soften and the sauce can separate after thawing. Making it a day ahead in the fridge works better.
Can I make it without mushrooms? Yes. Skip them and cook the shallot and garlic in the butter before adding the flour. The sauce will be milder.
How do I keep the onions from burning? Add the second half of the onions only for the last 5–10 minutes. If they brown too fast, cover the dish loosely with foil.
