Gluten-Free Green Bean Casserole (2024)

As a seasoned gluten-free cook, let me teach you how to make gluten-free green bean casserole, from scratch. This side dish rivals the old fashioned, classic green bean casserole you grew up on, but no one will realize it’s gluten-free. My version of this recipe skips canned soup and instead features a quick-to-make gluten-free substitute for cream of mushroom soup. Top the dish with homemade gluten-free fried onions and bake until bubbling.

Easy gluten-free green bean casserole with crispy onions

I know it sounds too good to be true. Is it possible to enjoy the same classic Thanksgiving side dish made without Campbells mushroom soup? Try better!

Once I learned how easythese gluten-free french fried onionswere to make, I knew this gluten-free side dish was back. Plus, I had already developed a condensed gluten-free substitute forcream of mushroom soupfor just this reason – as a homemade substitute in Thanksgiving casseroles.

The sauce for gluten-free green bean casserole comes together as easily as another favorite (and quick!) sauce of ours – gluten-free sausage gravy. The hardest part will be chopping the fresh mushrooms, which only requires a little prep and time.

Although traditional green bean casserole has always been one of the easiest Thanksgiving vegetable dishes, this green bean casserole without mushroom soup can be made in advance to save time on a hectic day.

If using the homemade fried onions, prepare them up to two days ahead of time. The mushroom cream sauce may be made up to three days before.

When ready to serve, simply mix together the cheese, soup, green beans, milk, and a handful of fried onions together. Sprinkle more onions on top and bake until cheesy and delicious. Enjoy a from-scratch casserole without canned soup, but with a taste just like Mom’s!

This casserole has decidedly become one of our favorite gluten-free side-dishes, and devoured equally by everyone at Thanksgiving, whether they follow a gluten-free diet or not! Read on to learn more easy tips to make this dish with success, including step-by-step photos, ingredient substitutions, and make-ahead instructions.

Ingredients notes

To make green bean casserole with mushrooms you will need to first make the quick, from scratch sauce. If you would like to skip this step you will need to substitute the sauce with gluten-free cream of mushroom soup (be sure to read labels carefully).

• Green Beans– Choose between canned, fresh green beans, or frozen. I recommend using the same as the classic dish you grew up on to mimic the taste. For frozen or fresh beans, use one pound cooked until just crisp tender. If using canned green beans, you will need three cans, drained.
• Gluten-FreeCream of Mushroom Soup– This recipe includes a homemade recipe, which can easily be adapted for dairy-free as well. As a shortcut, though, replace it with a can of gluten-free mushroom soup to save time.
• Gluten-Free Soy Sauce– This adds an extra layer of salty, umami flavor. My preferred brand is LaChoy or substitute liquid aminos or tamari as well.
• Milk– Helps thin out the creamy sauce. I prefer whole or 2% milk for best flavor, or replace with your preferred non-dairy milk.
• Cheese– Omit for a dairy-free recipe. I recommend sharp cheddar, but swiss, havariti, parmesan, or a combination may be used.
• Gluten-Free French Fried Onions– If you want something just as good as French’s, try the homemade recipe. To save an extra step, though, replace with store bought GF fried onions or use crushed pork rinds.

How To Make gluten-free green bean casserole

(Below shows step-by-step photos and modified instructions. For the complete recipe, along with ingredient amounts, scroll down to the recipe card.)

1. If using homemade GF fried onions, fry those first. Drain on a paper towel until ready to use. These can be made up to 2 days ahead of time and stored in an airtight container at room temperature.
2. For the homemade condensed soup, melt the butter in medium-high heat pan. Add the mushrooms, cooking and stirring until they are tender and the liquid has evaporated, about 6-7 minutes.
3. Add the garlic, salt, black pepper, onion powder to the mixture and saute for 30 seconds longer.
4. Whisk together chicken broth with cornstarch. Add to the mushrooms and simmer until thick, about 1 minute.
5. Stir in ½ cup milk and cook, stirring continuously for one minute longer. Set aside.
6. In a large bowl combine 1 ¼ cup condensed mushroom soup(save the remaining bit to add milk to for a future lunch!), cheese, milk, soy sauce, seasoned salt, pepper, and ½ cup fried onions. Gently stir to combine.
7. Spread green bean mixture in a 2 quart casserole dish (11X7, 9X9, or 8X8 dish will work). Add the remaining fried onions on top.
8. Bake in a350ºFpreheated oven for 30-40 minutes, or until golden brown, bubbly and hot throughout. Serve immediately.

Are Green Beans Gluten-Free?

All vegetables in their natural form are gluten-free, including green beans. Whether you enjoy them freshly picked, steamed from frozen, or canned green beans, they are safe for a gluten-free diet.

If green beans are served in a sauce (cream of mushroom soup, for instance) or sprinkled with a topping, this is when you will need to use extra precaution. Sauces may be thickened with wheat flour or contain barley or malt extracts. Toppings may include breadcrumbs, crushed cereal, or other foods not safe for those with celiac.

size of baking dish

This recipe is baked in a 2 quart baking dish, which works for an 8X8, 9X9, or 11X7 inch dish. If you would like to double the recipe, spread the casserole in a 9X13 dish and bake for 5-10 minutes longer.

gluten-free fried onion topping

While the traditional French’s Onions are not gluten-free, you can easily makecrispy gluten-free onionsjust as good as the originals!

These can be prepared up to 2 days in advance and stored at room temperature in an airtight container. If they need they became less crisp during storage, heat on a dry baking sheet in a 350ºF oven until crisp.

Alternatively, store-bought gluten-free versions may also be used. These aren’t commonly stocked year round, but around Thanksgiving and Christmas Aldi, Walmart, Whole Foods, Trader Joe’s, and Sprouts do carry them.

Substitutes for fried onions

If you are short on time (it is the holidays after all!) there are gluten-free substitutes the fried onions. Sprinkle with store-bought or homemadegluten-free breadcrumbs, chopped almonds or nuts, crushed potato chips, or pork rinds, which also happen to be naturally gluten free.

substituting store-bought soup

While there are some retail gluten-free mushroom soup brands, such as Progresso, Walmart, Pacific Foods, and Amy’s, making your own condensed, homemade recipe takes minimal effort and yields better results.

Finding a condensed, ready-made mushroom soup is harder to come by and using dump and heat versions adversely affects the recipe. The contents are thinner and not as flavorful.

If you do use a store-bought brand in place of homemade, use a 10 ounce can and read the labels carefully. I recommend holding off adding extra milk to the recipe. Stir everything together and add milk if the green bean mixture needs to be thinner.

dairy free Modification

The beauty of this recipe is it can easily be adapted for dairy-free as well. Make the mushroom soup using non-dairy milk and vegan butter.

If using the homemade french fried onions, these may also be prepared using a non-dairy milk in place of the buttermilk.

When mixing together the casserole, replace the milk with a dairy-free version and omit the cheddar cheese. It only takes a few simple substitutions to enjoy a gluten-free dairy-free green bean casserole recipe!

make-ahead instructions

If making this recipe completely from scratch, with no canned soup, the components may be prepared ahead of time.

Homemade GF french fried onions may be prepared up to 2 days in advance and stored at room temperature in an airtight container. If they need they became less crisp during storage, heat on a dry baking sheet in a 350ºF oven until crisp.

Make the mushroom soup up to three days ahead of time and refrigerate in an airtight container. Remember, you will only need 1 ¼ cups of it, and the remaining makes the perfect portion for lunch.

When ready to serve, briefly warm the soup so it’s stirrable. It does not have to be hot, just warmed slightly. Mix the condensed soup, milk, cheese, seasonings, fried onions, and green beans together and transfer to a baking dish. Top with the remaining onions and bake for 40 minutes, or until heated through.

storing / reheating tips

If you have leftovers, be sure the casserole has cooled completely before storing. Transfer to an airtight storage container and refrigerate up to three days.

Reheat serving-size portions in the microwave at 50% until almost heated through, gently stirring occasionally. Finish by heating at full power until hot.

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