Classic Green Bean Casserole from Scratch

Green bean casserole is an American Thanksgiving classic. A combination of tender green beans coated in creamy mushroom sauce topped with crispy fried onions. The combination is surprisingly addictive and a Thanksgiving favourite.

The first time I heard of green bean casserole I thought it sounded strange. The first time I tried it I understood its popularity. Quite honesty you could put anything in a creamy mushrooms sauce and I would think it tasted delicious. But honestly, this recipe is.

It may be made from scratch (Campbell's original recipe is made with mushroom soup) but it's still a simple recipe. To make life even simpler I fry my onions in an air fryer. Less oil and mess.

As mentioned the taste combination is quite addictive. Creamy mushroom sauce with fresh tender green beans. The fried onions add crunch and a deep onion flavour. My Aussie readers may want to bookmark this recipe for the Sunday roast or when winter comes back around.

Sara xxx

Green Bean Casserole Ingredients

1. Onion: Brown, yellow or white onions can be used. Yellow onions are milder than brown, and white onions (often called salad onions) are slightly sweeter in taste. Or use packed fried cripsy onions like French's Fried Onions.
2. Green Beans: Fresh green beans, also known as French beans or haricot vert. Yes, you can use frozen green beans if you wish.
3. Mushrooms: I use large button mushrooms, but you could also use Swiss brown or flat mushrooms. Be aware if you use larger flat mushrooms your mushroom sauce will be darker due to the darker mushroom gills (underside of the mushroom).
4. Cream: Full cream thick cream is used. You can use light thick cream, or light evaporated milk to cut the fat content in this recipe.
5. Garlic: If your garlic cloves are large only use 2 cloves. You can substitute 1 teaspoon of crushed garlic from a jar.
6. Nutmeg: Adds a little warmth and spice to the green bean casserole. Don't be heavy handed a little nutmeg goes a long way.
7. Salt: To season. Omit if on a low salt diet.
8. Flour: Plain/all purpose flour used to thicken the mushroom sauce.
9. Butter: Unsalted is used in this recipe. If you do use salted butter, check the sauce before adding extra salt to season, it may not need it.
10. Pepper: Ground black pepper to season.
11. Chicken Stock: Substitute chicken stock with vegetable stock to make this a vegetarian dish.
12. Parmesan Cheese: Adds an extra little umpf and umami kick to the mushroom sauce. Not normally used in green bean casserole, you can leave it out if you wish. But I feel it really elevates the flavour of the creamy mushroom sauce
13. Panko Crumbs: Adds more crunch to the onions than regular bread crumbs. A little trick I picked up from Alton Brown's recipe.

Serving Suggestions

This may be a classic American Thanksgiving dish, but it doesn't need to be Thanksgiving to enjoy it. Perfect for a Sunday roast, winter indulgence, or even as a Christmas side dish.

• Obviously goes a treat alongside a Thanksgiving turkey. Maybe my smoked turkey with orange maple butter, or poached turkey breast with easy gravy?
• To change things up it could accompany a Christmas or Easter ham, like my rum and coke glazed ham, or old fashioned glazed ham.
• It's a great side for corned beef due to the creamy sauce.
• Plus it goes along well with some other side faves, parmentier potatoes, maple bacon brussels sprouts, and cheesy cauliflower.

How to Make Green Bean Casserole

Scroll to the bottom of the page for a printable version of this recipe.

Pre-heat air fryer for 5 minutes at 200°C/390°F Place sliced onions in a large bowl. Add flour, panko crumbs, salt, and pepper. Toss onions until coated.

Place a layer of onions in the basket of your air fryer. Depending on the air fryer size you will need to fry the onions in 2-3 batches in order to not to crowd them. Fry onions for 8 minutes. Moving and tossing them around halfway through frying.

Place onions on a cooling rack, repeat with remaining onions. By placing the "fried" onions on the cooling rack they will not go soggy. (Works if frying in oil too)

Bring a large pot of salted water to a boil. Add beans and cook for 2-3 minutes, until just tender. Drain beans in a colander and refresh by running the beans under cold tap water. Dry beans with a clean tea towel or kitchen paper and set them aside.

Alternatively, beans can be cooked in the microwave or steamed until tender.

Place frying pan/skillet over medium heat, add butter. Once the butter has melted add mushrooms, and cook for 5 minutes.

Add salt, pepper, and garlic and cook for a further 2 minutes. Be careful not to burn the garlic.

Sprinkle flour over the mushrooms. Stir flour through the mushrooms until evenly coated and flour is no longer visible.

Continue stirring the mushrooms while gradually adding half the chicken stock. Keep stirring until any lumps have dissolved. Pour in the remaining stock.

Add cream, parmesan, and nutmeg, stir until completely incorporated. Continue cooking the mixture for a further 5 minutes, stirring as it cooks, until the cheese melts and the sauce thickens.

The sauce is ready when you can draw a line with your finger through the sauce on the back of the spatula or wooden spoon. Add beans to the mushroom mixture and mix well.

Place bean mixture into a 2.5ltr/2.5 quart baking/casserole dish. Cover the top of the bean mixture evenly with fried onions.

Place the baking dish into the oven and bake for 15 minutes. It is ready when the bean casserole is bubbling around the edges and the onions are deep golden brown.

Make the Recipe Ahead of Time

You can make this recipe ahead of time. The trick is to keep the key components separated.

• Beans: Cook the beans, drain, and then plunge in a bowl of water with ice to stop them cooking. Dry the beans well with a clean tea towel or kitchen paper. Place beans in a ziplock bag, remove as much air as possible and seal. Store in the fridge for up to 2 days.
• Fried Onions: Make a day ahead. Store in an airtight container at room temperature (they will go soggy in the fridge).
• Mushroom Sauce: Make as per the recipe, but do not add the beans. Store sauce in an airtight container in the frdige for up to 2 days.
• On the Day: Place sauce in a large pan/skillet and warm on a medium heat. Once the sauce is warm add the beans and mix well. Place bean mixture in a baking tray/casserole dish and top with onions. Bake as per the reciipe.

Sara's Top Recipe Tips

Warm the Chicken Stock

Place the chicken stock in a small saucepan and warm it until it is just over lukewarm temperature. By adding warm stock to the mushroom flour mixture it will be less lumpy or lump free.

By adding warm liquid to the already warm mushroom they aren't going into shock. Warm liquid and warm mushrooms will mix together more easily to create the sauce. Cold liquid causes a hot mixture to seize slightly and that is what forms lumps.

Don't deeply brown the onions when air frying

The fried onions need to be just golden as they will continue to brown in the oven on top of the casserole. If onions start to brown too quickly when baking cover the baking dish loosely with aluminium foil. Remove foil for the final few minutes of baking to crisp them up again.

Couldn't be bothered frying onions?

That's okay, buy ready made crispy fried onions. French's Fried Onions are incredibly tasty and easily available in US supermarkets. Aussie readers click the link above to buy them from catch.com. Fried shallots are available in Asian grocers and the Asian aisle in Aussie supermarkets, they aren't as nice as French's but will do the job.

Alternatively, forgo the fried onions all together. Instead, top the green bean casserole with a mix of panko crumbs (1 cup) and grated parmesan cheese (½ cup).

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