Everybody thinks of green bean casserole as a Thanksgiving dish, and it is, but we love it anytime during the chilly season. It’s just that kind of cozy, comforting dish, the kind of dish you’d bring to a Christmas or holiday potluck, or serve as part of a special weekend dinner.
Making green bean casserole from scratch is easy. There’s no need to rely on canned soup. Instead, make a béchamel sauce – that’s just fat (in this case, butter), flour and milk – nothing fancy. You may know it as a white sauce. Simple stuff. This béchamel is enriched with heavy cream and chicken broth and then combined with bacon, mushroom, onion, red bell pepper and garlic.
When figuring out my version of green bean casserole, I had the most trouble finding a substitute for the Durkee French fried onions. I didn’t want to fry onions – I think this recipe has more than enough fat in it to go that route. I tried the roasting method that Alton Brown used in his recipe, but both times the onions cooked unevenly – some of the onions burned while others dried out. Both times, I tossed them. My oven could be to blame for those results.
Finally, I decided to toss the onions with olive oil, sprinkle them with garlic salt and roast them at a lower temperature. Then while they were still warm, I tossed them with panko bread crumbs and thyme. Now they were perfect.
The recipe is long and, as you can see below, you end up using a lot of pots, pans and bowls. But, oh my god, it’s so worth it. You can make it ahead of time and pop it in the oven before dinner. Or do parts – like roasting the onions, blanching the green beans or sautéing the mushroom mixture – ahead of time.
I really love these green beans.
Green Bean Casserole
You’ll need a sheet pan, medium bowl, pot or saucepan (to blanch green beans and to make béchamel), colander, large skillet (for mushroom mixture), whisk, and 9” x 13” baking dish or a dish of equal volume – it’s okay if it’s deeper than a 9” x 13”.
- 3 medium or 2 large sweet onions, thinly sliced
- 3 tablespoons (or more) olive oil
- Garlic salt or regular salt
- 1/2 cup panko breadcrumbs
- 1/2 teaspoon dried thyme or 1-1/2 teaspoons fresh thyme
- 2 pound green beans, trimmed, cut in half
- 4 slices bacon, chopped to 1/4” pieces
- 3-4 cloves garlic, minced
- 2 medium yellow onions, chopped
- 12 to 16 ounces cremini and/or shiitake mushrooms, sliced
- 5 tablespoons butter
- 5 tablespoons all-purpose flour
- 3/4 cup milk
- 3/4 cup heavy cream
- 1/2 cup chicken broth
- 1-1/2 teaspoons salt, or to taste
- 1 teaspoon Worcestershire sauce
- 1/4 teaspoon cayenne pepper
- Few pinches of nutmeg
- Freshly ground black pepper, to taste
- 1 cup grated sharp cheddar cheese
- Grated Parmesan – the amount depends on the size of your baking dish, you want enough to cover it.
Preheat sheet pan and oven to 325. Toss the onions with the olive oil in a bowl, separating the rings as you toss. Remove the hot pan from the oven and spread the onions on it. Sprinkle generously with garlic salt. Roast them for about 20-30 minutes, tossing them every 10 minutes during cooking. When they’re golden to brown, transfer them back to that same bowl. Toss them with the breadcrumbs and thyme, and set aside. Turn the oven up to 350.
Bring a pot or saucepan of lightly salted water to a boil. Add the green beans, and cook for about 5-7 minutes, depending on the thickness of the beans and how soft or crisp you like your beans. 6 minutes is perfect for me. Drain them in a colander and set aside.
Heat a skillet over medium heat, add bacon and cook for two minutes. Then, add a little olive oil and the onion, red bell pepper and mushrooms, and continue cooking for 3 to 5 minutes, or until the bacon is just about done (but not too crisp) and the onions have softened. Make room in the middle of the pan, add garlic, a touch more oil, and cook 1 minute, or until golden. Remove from heat and set aside.
In the saucepan or pot you used for the green beans, melt the butter over medium heat. Sprinkle flour into the pan and whisk immediately to evenly mix it into the butter. Cook for about two minutes, stirring regularly, then pour in the milk, cream and chicken broth. Continue cooking, whisking constantly, while sauce thickens, about 2 minutes. Add salt, Worcestershire, cayenne, nutmeg, and pepper. Then take off the heat and add the grated cheddar. Stir while cheese melts.
Stir the mushroom mixture into the béchamel, then stir in the green beans. Pour into a baking dish.
Bake at 350 degrees for 10 minutes. Pull out and top with the onions and Parmesan. Bake 10 minutes more or until the sauce is bubbly and top is golden, but not burnt.