Recipes › Green bean casserole from scratch
Green Bean Casserole From Scratch (Make It a Day Ahead)
Disclosure: this recipe contains Amazon affiliate links. As an Amazon Associate we earn from qualifying purchases, at no extra cost to you.
This is the green bean casserole everyone expects at Thanksgiving, just made with fresh beans and a quick homemade mushroom sauce instead of a can. It's still easy, and the best part is you can put it together a day early. You'll want a 2-quart casserole dish and a big skillet (both on Amazon) for the sauce.
Short answer: boil the beans 4 to 5 minutes and cool them in ice water, make a mushroom cream sauce thickened with a little flour, fold together, and bake at 375 °F for about 25 minutes, adding the crispy onions for the last 5. You can assemble it (without the onions) a day ahead and keep it in the fridge.
Green Bean Casserole From Scratch
Fits an 8x8-inch or 2-quart baking dish. Double it for a 9x13-inch dish and add about 10 minutes to the baking time.
Ingredients
Beans
- 1 1/2 pounds (680 g) fresh green beans, ends trimmed, cut into 2-inch pieces
- 1 tablespoon salt, for the cooking water
Mushroom sauce
- 3 tablespoons unsalted butter
- 8 ounces (225 g) cremini or white mushrooms, sliced
- 1 small onion, finely chopped
- 2 cloves garlic, minced
- 1/2 teaspoon salt
- 1/4 teaspoon black pepper
- 3 tablespoons all-purpose flour
- 1 cup (240 ml) chicken or vegetable broth
- 1 cup (240 ml) whole milk or half-and-half
- 1/2 cup (45 g) grated Parmesan (optional)
Topping
- 1 1/2 cups (about 70 g) crispy fried onions, store-bought
Instructions
- Bring a large pot of water to a boil and add the tablespoon of salt. Fill a big bowl with ice water.
- Boil the green beans for 4 to 5 minutes, until bright green and just tender. Drain, then plunge them into the ice water to stop the cooking. Drain well and pat dry.
- Melt the butter in a large skillet over medium-high heat. Add the mushrooms and cook, stirring now and then, until they've given off their liquid and start to brown, about 6 to 8 minutes.
- Add the onion, garlic, salt and pepper and cook 3 more minutes, until the onion is soft.
- Sprinkle in the flour and stir for 1 minute. Slowly pour in the broth, stirring, then the milk. Simmer, stirring, until the sauce thickens enough to coat a spoon, about 4 to 5 minutes. Stir in the Parmesan if using. Taste and add salt if needed.
- Fold the green beans into the sauce and spread everything in a buttered 8x8-inch or 2-quart baking dish. (To make ahead, stop here - see below.)
- Bake at 375 °F (190 °C) for 20 minutes, until bubbling at the edges.
- Scatter the crispy onions over the top and bake 5 more minutes, until the onions are golden. Serve hot.
Why this version works
- Fresh beans, cooked briefly. A short boil and an ice bath keep them green with a little bite, so they don't turn mushy in the oven.
- Browned mushrooms. Letting the mushrooms cook until they brown gives the sauce real flavor - the part a can can't match.
- A sauce that's thick enough. It should coat a spoon before it goes in the dish. Too thin, and the casserole turns watery.
- Onions on last. Added at the end, they stay crunchy.
How to make it ahead
Thanksgiving oven space is tight, so this is a good one to get done early:
- The day before: blanch the beans, make the sauce and assemble the dish. Let it cool a bit, cover tightly and refrigerate - within 2 hours of cooking.
- On the day: take the dish straight from the fridge, uncover, and bake at 375 °F for about 30 to 35 minutes, until hot and bubbling in the middle. Then add the onions and bake 5 more minutes.
Keep the crispy onions in their bag until the end, or they'll go soft. A good plan: when the turkey comes out to rest (see our roast turkey guide), turn the oven up to 375 °F and slide this in - it'll be ready soon after the turkey is carved.
Swaps and tips
- Frozen green beans: use about 1 1/2 pounds, thawed and patted dry. Skip the boiling - just fold them into the sauce.
- Vegetarian: use vegetable broth.
- Homemade crispy shallots: thinly slice 3 to 4 shallots, toss with a spoonful of flour and fry in a little oil until golden; drain on paper towels.
- Richer sauce: use half-and-half instead of milk.
- Feeding a crowd: double everything and bake in a 9x13-inch dish.
Storing and reheating leftovers
Refrigerate leftovers within 2 hours and eat them within 3 to 4 days. Reheat until it's hot all the way through - 165 °F on a food thermometer. The onion topping won't be crisp the second day; a few fresh onions on top help.
Frequently asked questions
Can I make green bean casserole the day before?
Yes. Assemble it without the onion topping, cover and refrigerate within 2 hours. Bake it the next day at 375 °F for about 30 to 35 minutes, then add the onions for the last 5.
Can I use frozen green beans?
Yes - thaw about 1 1/2 pounds and pat them dry. Skip the boiling step and fold them straight into the sauce.
Why is my green bean casserole watery?
Usually the beans were wet or the sauce was too thin. Dry the beans well and simmer the sauce until it coats a spoon before mixing.
How long do leftovers keep?
About 3 to 4 days in the fridge. Reheat to 165 °F.
Sources and further reading
- University of Illinois Extension: storing holiday leftovers - refrigerate within 2 hours, shallow containers
- Mississippi State University Extension: leftover food safety - 3-4 days, reheat to 165 °F
- Google Trends: Thanksgiving - green bean casserole among the most-searched Thanksgiving recipes
How this was written: A from-scratch take on the classic green bean casserole (the original was created in 1955 by Dorcas Reilly in Campbell's test kitchen, using canned soup). Our version swaps the canned soup for a simple homemade mushroom sauce. Leftover guidance comes from university extension food-safety pages. No nutrition numbers.