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A classic green bean casserole with all of the flavor but none of the gluten. This holiday casserole is a Thanksgiving and Christmas tradition in my house. Made with homemade cream of mushroom soup and crispy fried onions, it’s a recipe that is easy to make gluten-free, and everyone enjoys it!
Gluten-Free Green Bean Casserole Recipe
This gluten-free green bean casserole tastes just like the classic casserole that everyone makes during the holidays. It combines my gluten-free creamy mushroom soup, green beans, and sweet fried onions for a cozy and nostalgic side dish that’s perfect for family gatherings or holiday feasts.
Topped with golden, gluten-free fried onions, this casserole has the perfect mix of crunchy texture and savory flavor that keeps everyone coming back for more. I love how the fried onions add a light sweetness and a satisfying crunch to every bite. Since most of my family (myself included) is dairy-free, most of my recipes have a dairy-free option and this is no different!
Ingredients
- Sweet Onions: I used white onions for the crunchy fried onions.
- Milk: Milk is used to make the buttermilk which allows the flour and cornstarch bind to the onions and to add another creamy layer to the casserole. For a dairy-free/ vegan option use your favorite substitute.
- White Vinegar: White vinegar and milk are mixed together to create a homemade buttermilk.
- Gluten-Free All-Purpose Flour: My favorite is Pillsbury. You can use what you have on hand or your favorite brand.
- Cornstarch: Cornstarch adds a light, crunchy texture to the crispy onions.
- Gluten-Free Seasoned Salt: A blend of savory seasonings and salt that balances the flavors of the dish
- Black Pepper: To enhance the flavor of the dish.
- Vegetable Oil: Used as frying oil for the onions. You can use any oil with a high smoke point like avocado oil or canola oil.
- Gluten-Free Cream of Mushroom Soup: I used my gluten-free cream of mushroom soup recipe, which also has a dairy-free and vegan option. Feel free to use any gluten-free soup.
- Worcestershire Sauce: Provides a savory boost to the dish that balances the creamy sweetness.
- Whole Green Beans: I use canned green beans, but you can also use fresh or frozen.
Tips and Suggestions
- Carefully use a mandoline to slice the onions thin. This may be easier than using a knife. Alternatively, make sure your knife is very sharp.
- If you do not want to make your own gluten-free fried onions, and you can’t find them at the grocery store you could use crushed Funyuns instead. Funyuns are gluten-free, but they are not dairy-free.
- Check your fry oil before adding all the onions. Use a thermometer to enusre the oil reaches a temperature of 375 degrees F, and test it by adding one onion first. If the onion sizzles and floats to the top, your oil is ready for frying. If it sinks or doesn’t bubble much, the oil needs to heat up a bit more.
- If you’re using fresh green beans, trim, cut, and briefly boil or microwave them. For frozen green beans, cook them until tender-crips, about 5 minutes.
- You can make it dairy-free/ vegan by substituting milk for the cream of mushroom soup recipe and the onion toppings. You may have to make a homemade dairy-free soup.
- This green bean casserole recipe can be made in advance. I’ll prepare it a couple of days before a holiday to give myself more time on the day. Just prepare the casserole as directed but place the onions in an airtight container or plastic bag. Add the onions before baking and bake as directed. Allow the casserole to come to room temperature, about 15 minutes or you could add another 5-10 minutes to the baking time if it is still really cold.
Serving Suggestions
I have this gluten-free green bean casserole on my holiday table every year alongside a roasted turkey, honey-glazed ham, or a juicy prime rib.
Storage Instructions
Store leftovers in an airtight container in the refrigerator for up to 3-4 days.
For longer storage, freeze the casserole (without the fried onion topping) in a freezer-safe dish for up to 2 months. When freezing, let it thaw overnight in the fridge before reheating.
Always add the fried onions just before baking or reheating to keep them crispy!
More Gluten-Free Side Dish Recipes
- Gluten-Free Southern Baked Macaroni and Cheese
- Easy Gluten-Free Stuffing {Dairy-Free}
- Gluten-Free Sweet Potato Casserole {Dairy-Free Option}
Gluten-Free Green Bean Casserole Recipe
Ingredients
Gluten-Free Fried Onions
- 2 large sweet onions, thinly sliced
- 1 cup milk, dairy-free use almond, cashew or coconut milk
- 1 tbsp white vinegar
- 1/2 cup gluten-free all-purpose flour, I like Pillsbury gluten-free flour
- 1/2 cup cornstarch
- 1 tbsp gluten-free seasoned salt
- 3 cups vegetable oil
Casserole
- 1 (10.5 oz) can gluten-free cream of mushroom soup, Or 1 1/4 cup of my homemade gluten-free cream of mushroom soup {dairy-free option}
- 1/4 cup milk, dairy-free use almond, cashew or coconut milk
- 1 teaspoon gluten-free Worcestershire sauce, I like Lea and Perrins. For vegan use your favorite vegan and gluten-free Worcestershire sauce
- 1/8 teaspoon ground black pepper
- 2 (14.5 oz) cans whole green beans, drained
Instructions
Gluten-Free Fried Onions Step
- Thinly slice onions.
- Add milk (or dairy-free milk) and vinegar to make buttermilk to a pie pan or shallow dish and allow to sit for 2-3 minutes.
- Add the onions to the buttermilk and soak for 5-10 minutes.
- In a plastic storage bag add the gluten-free flour, cornstarch, seasoned salt, and mix well.
- In a large pan heat vegetable oil to 375°F degrees.
- Add the buttermilk soaked onions to the flour mixture in the plastic bag and turn the bag over and over until the onions are well coated.
- Add the battered onions to oil, frying in batches, until golden brown.
- Remove the onions from oil with a slotted spoon and drain on a paper towel-lined plate.
Casserole
- Pre-Heat your oven to 350°F and spray a 1 1/2-quart casserole dish with gluten-free cooking spray.
- In a small bowl mix together the gluten-free cream of mushroom soup (or gluten-free and dairy-free soup), gluten-free Worcestershire sauce, milk (or dairy-free milk) and pepper until smooth.
- Add the drained canned green beans to the casserole dish.
- Pour the soup mixture over the green beans.
- Sprinkle 1 cup of the gluten-free fried onions over the soup and gently stir to mix the ingredients together.
- Place on the middle rack and bake for 25 minutes.
- Sprinkle with the remaining gluten-free fried onions and bake for another 10-15 minutes until bubbly and the sides of the casserole start to brown.
- Store leftovers in an air-tight container and refrigerate.
- Leftovers can be re-heated the microwave or oven.
Notes
- Carefully use a mandoline to slice the onions thin, this may be easier than using a knife. Alternatively, make sure your knife is very sharp.
- If you do not want to make your own gluten-free fried onions, and you can’t find them at the grocery store you could use crushed Funyuns instead. Funyuns are gluten-free, but they are not dairy-free.
- Check your fry oil before adding all the onions. Use a thermometer to enusre the oil reaches a temperature of 375 degrees F, and test it by adding one onion first. If the onion sizzles and floats to the top, your oil is ready for frying. If it sinks or doesn’t bubble much, the oil needs to heat up a bit more.
- If you’re using fresh green beans, trim, cut, and briefly boil or microwave them. For frozen green beans, cook them until tender-crips, about 5 minutes.
- You can make it dairy-free/ vegan by substituting milk for the cream of mushroom soup recipe and the onion toppings. You may have to make a homemade dairy-free soup.
- This green bean casserole recipe can be made in advance. I’ll prepare it a couple of days before a holiday to give myself more time on the day. Just prepare the casserole as directed but place the onions in an airtight container or plastic bag. Add the onions before baking and bake as directed. Allow the casserole to come to room temperature, about 15 minutes or you could add another 5-10 minutes to the baking time if it is still really cold.
- Store leftovers in an airtight container in the refrigerator for up to 3-4 days.
- For longer storage, freeze the casserole (without the fried onion topping) in a freezer-safe dish for up to 2 months. When freezing, let it thaw overnight in the fridge before reheating.
- Always add the fried onions just before baking or reheating to keep them crispy!
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
How to make Gluten-Free Green Bean Casserole Step-by-Step
Slice 2 large sweet onions thinly using a sharp knife or mandoline.
Grab a pie pan or shallow dish and add 1 cup of milk and 1 tbsp white vinegar. Allow the milk mixture to sit for 2-3 minutes. We’re creating our buttermilk base here.
Add the 2 thinly sliced onions to the buttermilk dish and soak for 5-10 minutes.
Using a large plastic storage bag, add ½ cup gluten-free all-purpose flour, ½ cup cornstarch, and 1 tbsp seasoned salt. Mix well.
Heat 3 cups of vegetable oil in a deep pan or pot. Bring the oil to 375 degrees F. Use a thermometer to check. Add the 2 cups of soaked onions to the flour mixture in the plastic bag. Seal the bag and turn it over and over until the onions are well coated.
Fry the onions in batches by adding them to the frying oil. Remove the onions using a slotted spoon when they’ve reached a golden brown. Place the onions on a paper-towel lined plate to drain and set aside for later.
Preheat your oven to 350 degrees F and use cooking spray to grease a 1 ½ quart casserole dish. In a small bowl, add 1 10.5 oz can or 1 ¼ cups of my homemade mushroom soup cream. Mix in 1 tsp gluten-free Worcestershire sauce, ¼ cup of milk, and ⅛ tsp black pepper. Stir until smooth.
Drain 1 can of green beans and add them to the greased casserole dish.
Then, pour the cream of mushroom soup mixture over the green beans.
Next, sprinkle 1 cup of the fried onions over the soup and stir to mix the ingredients together.
Place the casserole dish in the oven on the middle rack and bake for 25 minutes.
Sprinkle the remaining gluten-free fried onions on top and bake for another 10-15 minutes. The casserole should be bubbly and golden brown.
Going to try this one!
Hi, Audrey! This will be the 2nd year we are making this for Thanksgiving. Last year it was enjoyed by all, gluten-free vegan, or not! And we can make it super clean – good for everybody!
Last year I made 2 large onions, was frying them in batches for eons, and ended up with way too many fried onions! I guess the large onions they’re growing these days are ginormous!
So your recipe states to put 1 cup in the mixture. How many do you then end up sprinkling on top? 1/2 cup? 3/4 cup?
Hi Melody, we sprinkled all of the leftovers on top. However, if you find you have too many, we recommend frying just 1 large onion instead!
This is my 3rd year making this and it is always amazing! I have to hide the onions from family so they don’t eat them all before it’s done.
This is now a family favorite! So delicious and incredibly easy to make. The gluten-free dairy-free onion rings on top were so good that I had to stop my husband from coming by in the kitchen and eating a handful before they went on the green bean casserole in fear I’d not have enough to put on top of the casserole. Thank you for sharing!!!