Some holiday dishes can be made ahead and this Fresh Green Bean Casserole recipe is made with fresh green beans, a creamy homemade sauce, and topped with crispy onions, this dish is sure to become a new favorite. It is ideal to whip up and then simply reheat in an oven just prior to serving for a fuss free and healthy side dish for those family gatherings.
You could prep the mushroom and sauce portions two days ahead and refrigerate making prepping this a breeze on the day. Or you could make the entire dish except for that topping a whole day ahead and heat in your oven with the toppings just before serving.
This entire dish relies on homemade meaning you control every ingredient and element in it and that means if you like a different hardy herb, toss that in or double the mushrooms if you want it to be super mushroom heavy, work to your palate and this will still be a stellar dish!
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Why you'll love this
By using fresh green beans, this casserole offers a vibrant and crisp texture, elevating the overall taste and quality of the dish. Say goodbye to canned green beans and experience the difference fresh ingredients can make.
Homemade Creamy Sauce
Unlike traditional recipes that rely on canned soup, this recipe features a homemade creamy sauce. Made with simple ingredients like butter, flour, and milk, it adds a rich and velvety texture to the casserole, ensuring a decadent and satisfying bite every time.
The crowning glory of this casserole is the irresistible crispy onion topping. Baked to golden perfection, these crunchy onions add a delightful contrast of texture and a burst of savory flavor. They create a harmonious balance that will make this dish a standout at any dinner table.
Ingredients and substitutions for the best Fresh Green Bean Casserole
- Green Beans: The variety used here is known as a French Green bean, Haricots Verts or Filet Beans - they're thinner than other types of string style beans and have a great crunch. You could replace with standard green beans.
- Mushrooms: Brown or button mushrooms are ideal in size and flavor. You could replace with portobello mushrooms.
- Garlic & Rosemary: Minced garlic and finely chopped rosemary add depth of flavor and additional savoriness to the dish, if you don’t like one or both, feel free to omit.
- Butter: Salted butter was used here, though could be substituted with non salted or even non dairy butter in equal measure, though it is not guaranteed what the texture will result in.
- Flour: Plain flour was used for the sauce, but could be replaced with bread flour due to the amount used. A gluten free flour mix that is similar to plain flour is recommended if going gluten free as I cannot guarantee the overall result with all gluten free flours.
- Milk: Whole milk was used for the béchamel sauce as it results in a super creamy rich sauce, but you can absolutely substitute with non dairy milk in equal measure, though the results cannot be guaranteed.
- Cheese: Cheddar and parmesan cheeses were used here for a subtle and salty flavor, you could substitute the cheddar with any other mild cheese such as edam or polvorone. If you choose not use parmesan, it’s recommended adding 1 further teaspoon sea salt to make up for the lack of saltiness the parmesan adds.
See recipe card for quantities.
How to make Fresh Green Bean Casserole:
Roast em: Roast your mushrooms and garlic.
Set aside: Remove the roasted mushrooms and set aside.
Blanche your beans: Blanche em until lightly cooked.
Béch-a-mel: Make your béchamel.
Stir: Stir the beans, mushrooms and béchamel together in your baking dish.
Cover and bake: Cover your baking dish with aluminum foil and bake.
Finish: Remove the foil, toss over the onions and cheese and bake until golden.
Serve up: Serve up and dig in!
Equipment needed to make this
Baking dishes: For minimal effort on the mushrooms, we bake them which requires a small baking dish. You could use a frying pan instead. For the final green bean casserole, we also need a baking dish.
Saucepan: For the bechamel sauce and to blanche those green beans.
Whisk: To create a nice smooth creamy sauce.
FAQ's for the best Fresh Green Bean Casserole
Shallots are best here and for the quantity you need in this recipe, you’ll want to peel 2 large shallots and slice into half moons.
Pour 1 cup neutral oil (sunflower is best) into a small saucepan on medium high heat until you see ripples across the oil.
Toss in 1 handful of the onions where they should be simmering in the oil and stir to cook evenly for 1 ½ - 2 minutes until lightly golden.
Remove and place on paper towels to drain.
Repeat with the remaining shallots in handfuls until all are crispy.
These are best covered and consumed within 1 day of being made.
While we highly recommend using fresh green beans for the best texture and flavor, you can substitute canned green beans, if needed. However, keep in mind that the overall taste and texture may differ slightly.
Yes, you can freeze the leftovers of this Fresh Green Bean Casserole. Allow it to cool completely, then transfer it to an airtight container or freezer-safe bag. It can be stored in the freezer for up to 3 months. To reheat, thaw it overnight in the refrigerator and then bake it until heated through.
More side recipes you’ll enjoy
Fresh Green Bean Casserole
- 250 grams / ½ pound button or brown mushrooms sliced
- 4 garlic cloves peeled and finely sliced
- 35 grams / 2 ½ tablespoons butter
- 35 grams / 4 tablespoons plain flour
- 1 teaspoon salt
- 350 milliliters / 1 ½ cups milk
- ½ teaspoon American mustard
- 1 tablespoon dried rosemary
- 700 grams / 1 ½ pounds fresh green beans trimmed
- ⅓ cup crispy onions to homemake them, see notes
- 22 grams / ¼ cup parmesan grated
- Preheat the oven to 220C/425F and toss the mushrooms and garlic into a baking dish.
- Place in the oven until the water runs out and they are brown, approximately 15 minutes with tossing every 5 minutes to ensure even cooking.
- Remove and set aside.
- Meanwhile, place a heavy saucepan on high heat and fill with enough water to blanche your green beans and add 2 teaspoons salt.
- Once it has reached a rolling simmer, toss in a handful of green beans for 1 ½ minutes until green and ever so slightly soft.
- Remove and drain and place into your baking dish.
- Meanwhile, to make the béchamel, place the butter in a small saucepan on low heat and add in the flour.
- Whisk until smooth and no dry portions remain on the edges.
- Add in ¼ of the milk and whisk until fully combined and smooth.
- Cook until thickened and lightly simmering, repeat with a further ¼ of the milk in batches until thickened and a sauce that still runs freely off your whisk.
- Add in the mustard and dried rosemary and stir to combine.
- Toss the garlic mushrooms over your green beans and pour over the béchamel over the entire baking dish.
- Toss to coat everything evenly and cover with aluminum foil.
- Bake for 20 minutes, remove the foil and sprinkle over the crispy onions and grated parmesan and return to the oven for 15 minutes.
- Remove and allow to cool for 5 minutes before serving.
- Dig in!
- Homemade crispy onions: Shallots are best here and for the quantity you need in this recipe, you’ll want to peel 2 large shallots and slice into half moons.
- Pour 1 cup neutral oil (sunflower is best) into a small saucepan on medium high heat until you see ripples across the oil.
- Toss in 1 handful of the onions where they should be simmering in the oil and stir to cook evenly for 1 ½ - 2 minutes until lightly golden.Remove and place on paper towels to drain. Repeat with the remaining shallots in handfuls until all are crispy.
- These are best covered and consumed within 1 day of being made.
- Using canned beans: You can substitute with canned green beans, if needed.
- Make ahead elements of this dish: You can absolutely oven roast the mushrooms 2-3 days ahead of assembling, simply cover and refrigerate until you need them.
- Freezing the casserole: Allow it to cool completely, then transfer it to an airtight container or freezer-safe bag. It can be stored in the freezer for up to 3 months. To reheat, thaw it overnight in the refrigerator and then bake it until heated through.
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