Green Bean Casserole
Meet the star of your holiday table – the ultimate green bean casserole. The green beans are fresh and bright, and baked in an ultra-flavorful mushroom cream sauce, a velvety mixture that laced with crispy fried onions and thyme. Baked under a canopy of extra crispy fried onions, this is the quintessential vegetable side dish. And since it’s easy to make and pleases the entire crowd, there’s no need to relegate this dish to the holidays.
This recipe was written for the Arizona Republic.
Here’s what you’ll need to make this incredible green bean casserole
- Green beans. Hands down, fresh produce is best here. You simply can’t beat the color and flavor of fresh green beans, and they deliver the delightful snap you can’t get from frozen or canned green beans. That said, you can certainly substitute frozen and canned green beans. When using frozen, blanch them for 1 minute instead of 4 (because they’ve already been blanched prior to freezing). When using canned green beans, drain them well and pat them dry before using; there’s no need to blanch them.
- Mushrooms. I love cremini (baby bella) mushrooms in this green bean casserole. Cremini mushrooms deliver much more of an earthy, umami flavor than white button mushrooms. If desired, you may use white button mushrooms instead.
- Tamari sauce or soy sauce. While an Asian soy-based sauce might seem like an odd addition to this classic American dish, it’s not. Tamari (and soy) bring out the mushroom’s umami-ness, adding extra depth of flavor.
- Olive oil. We use olive oil to sauté the mushrooms and as the “fat” needed to create the roux with the flour (the roux thickens the sauce).
- Milk. Milk is used as the base of the cream sauce. I highly recommend using whole milk for its unrivaled richness.
- Flour. All-purpose flour is used to thicken the milk and transform it into a cream sauce. For a gluten-free dish, use your favorite all-purpose, gluten-free flour blend that has a 1:1 (measure to measure) ratio.
- Garlic and thyme. Garlic and thyme are used as the savory aromatics in the cream sauce.
- Dijon mustard. The slight kick of Dijon mustard adds tang to the rich cream sauce. You don’t need much – in fact it’s barely detected; it’s used to elevate the nuances of the other ingredients.
- Parmesan cheese. Good-quality parmesan cheese adds nuttiness to the sauce while complementing the sweetness of the mushrooms and green beans.
- Crispy fried onions. The store-bought variety is best here! The onions maintain their crispness and add great flavor and crunch.
- Salt and black pepper. We use salt in the blanching water (to season the green beans), and we use black pepper to enhance the dish and make all ingredients more prominent. If possible, use freshly ground black pepper for the best flavor.
Tips for a flawless green bean casserole
- Blanch your green beans for 4 minutes. The first step in this recipe is blanching your green beans. Once trimmed, blanch the green beans in salted water for 4 minutes. This pre-cooking step ensures that the vegetable is delightfully fork-tender after baking.
- Plunge your blanched green beans in an ice bath. Once your green beans have cooked for 4 minutes in boiling water, drain and immediately transfer them to an ice water bath to halt further cooking. We don’t want mushy green beans in our casserole.
- Make sure your green beans are dry before assembling the casserole. No one wants a watery green bean casserole, so after the ice bath, drain your green beans and lay them out on paper towels to dry.
Make ahead instructions. This green bean casserole can easily be prepped in advance, which makes it an excellent option for holiday meal planning. To prep ahead, prepare the casserole as directed; up until the baking step (without the fried onion topping). Cover the casserole dish with plastic wrap and refrigerate for up to 2 days. Remove the dish from the refrigerator 30 minutes before baking. Proceed as directed.
How to store leftovers. This green bean casserole recipe is at its peak when it comes out of the oven, when the filling is bubbly, and the topping is crispy. That said, you can store leftovers in the refrigerator for up to 3 days. Reheat leftovers in a 350-degree oven until hot all the way through. Since the fried onion topping will lose its crunch when stored, if desired, add more fried onions to the top before reheating.
Variations and additions. This recipe is complete perfection as is, but there are always additions and variations to consider.
- Use cheddar cheese instead of parmesan cheese or use an equal amount of each.
- Use roasted garlic instead of fresh garlic.
- Use fresh or dried oregano instead of fresh thyme.
- Add crushed red pepper flakes or hot sauce to the filling for a little kick.
- Double the amount of mushrooms for a more mushroom-heavy casserole.
Green Bean Casserole
Ingredients
- 1 1/2 pounds green beans, ends trimmed and halved crosswise
- 2 tablespoons olive oil
- 8 ounces mushrooms, cremini or button, thinly sliced
- 2 tablespoons tamari sauce, or soy sauce
- 4 cloves garlic, minced
- 1 tablespoon fresh thyme leaves
- 1/4 cup all-purpose flour
- 2 1/2 cups milk, preferably whole milk
- 1 teaspoon Dijon mustard
- 1/2 cup grated Parmesan cheese
- Salt and freshly ground black pepper
- 1 3/4 cups crispy fried onions, divided
Instructions
- Preheat the oven to 350 degrees. Coat a 13×9-inch baking pan with cooking spray or a thin layer of olive oil.
- Bring a large pot of salted water to a boil. Add the green beans and blanch for 4 minutes. Drain and immediately transfer the green beans to a bowl of ice water to prevent further cooking. Drain and transfer the green beans to paper towels to dry.
- Heat the olive oil in a large skillet over medium heat. Add the mushrooms and cook for 5 to 7 minutes, until tender and releasing liquid. Add the tamari sauce, garlic, and thyme and stir to combine.
- Add the flour and stir to coat.
- When the flour is fully incorporated, add the milk and Dijon mustard and bring to a simmer, stirring constantly. Reduce the heat to medium-low and simmer for 5 to 7 minutes, until the sauce thickens to a gravy-like consistency. Fold in the parmesan cheese and 1/4 teaspoon black pepper. Fold in the green beans and 1 cup of the crispy fried onions.
- Transfer the mixture to the prepared pan and bake for 20 to 25 minutes, until bubbly.
- Top with the remaining 3/4 cup of crispy fried onions and bake for 5 to 7 more minutes, until golden and crisp on top.
- Serve hot.