This green bean casserole recipe skips the canned soup. Chris Morocco’s take on the classic Thanksgiving side pairs fresh green beans and deeply browned crimini mushrooms with a garlicky Parmesan béchamel. As for the topping, French’s fried onions are iconic for good reason, and they are staying right where they belong.
Give the mushrooms room to brown, salt the blanching water generously (like you would for cooking pasta), and taste the mushrooms and sauce before assembling. As written, you can cook the mushrooms and make the sauce at the same time. To save a pan, cook the mushrooms first, then transfer them to a plate and make the béchamel in the same pan, scraping up all the browned bits.
Watch Chris make green bean casserole
For the rest of the spread, turn to our classic Thanksgiving menu →
Can I make green bean casserole ahead of time?
Yes. Blanch the green beans, cook the mushrooms, and make the sauce up to 1 day ahead; cool and refrigerate them separately. Assemble and bake the day you plan to serve it, adding the fried onions during the final few minutes of baking.
We don’t recommend freezing the assembled casserole—the cream sauce can separate, and the beans turn mushy after thawing and reheating.
How do I keep the cream sauce from separating?
Don’t overreduce it. Once the béchamel is thick and bubbling, take it off the heat before whisking in the garlic and Parmesan. Boiling off too much liquid can cause the fat to separate. Stick with the recipe’s amount of Parmesan, too—extra cheese can contribute to a broken sauce.
Can I use frozen green beans?
Blanched, fresh beans are our first choice, but readers have reported success with frozen petite and French-cut beans. We haven’t tested the swap, but recommend thawing them overnight in your refrigerator and straining the excess liquid before continuing.
Can I make this green bean casserole gluten-free?
We haven’t tested a gluten-free version, but our editors suggest replacing the all-purpose flour with a gluten-free flour blend. You’ll also need to seek out gluten-free fried onions, or try our flourless Crispy Fried Shallots.
Recipe information
Total Time
1 hour 35 minutes
Yield
8 servings
Ingredients
2
2
1
6
4
2
1¼
1
4
½
¾
Need to make a substitution?
Preparation
Step 1
Place rack in middle of oven; preheat oven to 375°. Working in batches, cook 2 lb. fresh green beans in a large pot of boiling salted water until bright green and halfway to tenderness, about 3 minutes per batch. Drain and let cool; trim stem ends.
Step 2
Heat 1 Tbsp. extra-virgin olive oil in a large skillet over medium-high. Cook ½ lb. crimini mushrooms, sliced, without stirring, until golden brown underneath, about 2 minutes. Toss and continue to cook, tossing occasionally, until browned on both sides, about 3 minutes more. Add 2 Tbsp. unsalted butter and 2 large thyme sprigs to pan. Cook, tossing occasionally, until butter browns and mushrooms are dark brown and very tender, about 4 minutes longer. Season with kosher salt and transfer to a plate. Repeat with 2 Tbsp. unsalted butter, salt, and remaining 1 Tbsp. extra-virgin olive oil, ½ lb. crimini mushrooms, sliced, and 2 large thyme sprigs.
Step 3
Melt remaining 2 Tbsp. unsalted butter in a large saucepan over medium-low. Whisk in 2 Tbsp. all-purpose flour and cook, whisking occasionally, until roux is golden brown and smells mildly nutty, about 4 minutes. Whisk in 1¼ cups whole milk and 1 cup heavy cream. Increase heat and bring to a simmer, whisking often, and cook until béchamel sauce is thick and bubbling, about 5 minutes. Remove from heat and whisk in 4 garlic cloves, finely grated, and ½ cup grated Parmesan; season with salt and freshly ground pepper.
Step 4
Arrange green beans and mushrooms in a 2-qt. baking dish. Pour sauce over bean mixture (it may not look like enough, but it will get saucier as it bakes). Cover tightly with foil and bake until sauce is bubbling, 25–30 minutes. Uncover and continue to bake until casserole is lightly browned on top and around the edges, 15–20 minutes longer. Top with ¾ cup French’s fried onions and continue to bake just until onions are slightly darker and fragrant, about 3 minutes. Let sit 10 minutes to set before serving.
Editor’s note: This green bean casserole recipe first appeared in November 2016 as part of BA’s Best, our vault of the Test Kitchen’s definitive takes on iconic dishes. Head this way for more of our go-to Thanksgiving recipes →