Our easy Gluten-Free Green Bean Casserole recipe is made with a homemade sauce that puts it over the top. This cozy Thanksgiving favorite has all the classic flavor you love, simply made gluten-free!

A pan of gluten-free green bean casserole with crispy onionsa

Gluten-Free Green Bean Casserole With Homemade Sauce!

Thanksgiving dinner is nearly here, and for so many of us, it wouldn’t be Thanksgiving without this classic side dish! Our homemade gluten-free green bean casserole recipe has all the flavor you love in traditional green bean casserole, with a few bonus benefits:

It’s EASY. Simple ingredients, and simple techniques are the name of the game, even though we’re skipping the canned soup. We’re talking slicing, boiling, stirring. That’s it! No fancy skills required.
It’s DELICIOUS. Tender green beans, a savory, creamy sauce with rich mushroom flavor (+a few flavor boosts!), plus the crispy fried onion topping that make this such a classic holiday side dish.
It’s GREAT FOR MAKING AHEAD. Thanksgiving prep is no joke, so it’s great to have recipes you can make in advance. This easy green bean casserole recipe comes with prep-ahead tips to save you time on the big day!

I hope you love it as much as we do! Happy cooking! xo, Emily

Gather Your Ingredients

Our homemade gluten-free green bean casserole recipe is made without cream of mushroom soup, but it’s still REALLY easy to make, thanks to a list of simple ingredients. Here’s what you’ll need to get started:

Ingredients for gluten-free green bean casserole

Frozen Green Beans. You can absolutely use fresh green beans here, but I find that frozen green beans are easy to keep on hand, guaranteed fresh, and cook up beautifully for this green bean casserole. We boil them JUST till tender, then stop the cooking process with an ice bath, which keeps the texture and bright green color looking great. I like cut green beans, but feel free to use french-style green beans, if you prefer!
Butter. To start our homemade mushroom sauce, you’ll need some butter. Salted butter or unsalted butter works here, though I usually use salted.
Mushrooms. Next, some fresh mushrooms! I use white button mushrooms, but baby bella mushrooms also work. Wipe them clean, and slice thinly so they cook evenly.
Garlic, Salt & Pepper. Next, to build flavor, we’re adding fresh garlic, along with kosher salt and black pepper. Simple, but delicious!
Gluten-Free Flour. Then, we’ll add gluten-free 1:1 flour to help thicken the sauce. Toasting it a bit first helps mellow out the flavor. If you need to use cornstarch instead, see the FAQ below!
Chicken Broth & Gluten-Free Tamari. Then, we’ll add chicken bone broth and a splash of gluten-free tamari (gluten-free soy sauce) for some umami flavor. It pairs beautifully with the mushrooms and adds delicious depth to this homemade cream sauce.
Heavy Cream & Fresh Parmesan. Lastly, we finish the creamy mushroom sauce off with some heavy cream and fresh parmesan. They add the perfect creaminess and an extra layer of flavor that beats canned soup any day!
Gluten-Free Crispy Onions. The star of the show! Since we’re making homemade sauce, I’m taking one shortcut here with store-bought gluten-free crispy fried onions. Regular french fried onions are NOT gluten-free, so keep an eye out for celiac safe, gluten-free crispy onions at the grocery store. Sprouts brand or Whole Foods brand is my favorite, but Golden Farms brand is also good. You can find them at Sprouts, Thrive Market or Amazon, along with places like Wegmans, HEB, or HyVee! See the FAQ for a from-scratch option, if you need one!

How To Make Gluten-Free Green Bean Casserole, Step By Step

As always, you can find the full recipe with ingredient amounts, detailed instructions, and tips in the recipe card below.

Making homemade gluten-free green bean casserole step by step

Preheat & Prep. To start, preheat the oven to 375 degrees F. Set out a glass or ceramic 9×13 casserole dish.
Start The Green Beans. Bring a large saucepan of water to a boil, then add green beans and cook 5-7 min or until tender with just a tiny bite left. While the beans cook, prepare an ice bath by filling a large bowl of water with ice and cold water. When the beans are finished cooking, drain them, then quickly add to the ice bath while you finish the mushroom sauce. This will stop the cooking process and help preserve their vibrant color.
Start The Mushroom Sauce. In a large skillet, melt butter over medium heat. Add the mushrooms and cook 8-10 min, or until golden brown and tender.
Build Flavor. Add minced garlic, salt, pepper, and gluten-free flour and cook 1-2 minutes until fragrant.
Thicken & Finish The Sauce. Pour chicken broth and gluten-free tamari into the skillet and stir, making sure to scrape up any browned bits from the bottom of the pan. Cook 3-5 minutes over medium heat until thickened. Turn off the heat and stir in cream and parmesan cheese. Stir until cheese is melted and the sauce is evenly blended.

Combine. Remove the green beans from the ice bath and drain well. In a large bowl (or your skillet if you have room!), combine mushroom sauce and green beans and stir to coat evenly.
Layer. Pour green bean mixture into your prepared pan and smooth into an even layer. Sprinkle the stop of the casserole with crispy onions.
Cover + Bake. Tightly cover the pan with aluminum foil and bake 20-25 minutes, or until the sauce is bubbling around the edges of the pan. Remove the foil then bake and additional 5 minutes to toast the onions. Serve warm and store leftovers in an airtight container in the fridge 3-4 days.

All the classic flavor you love, simply made gluten-free! Our gluten-free green bean casserole recipe is made with an easy homemade sauce you'll LOVE. It's the perfect Thanksgiving side dish to try!

Tips For Prepping Green Bean Casserole In Advance

This homemade green bean casserole recipe can be largely prepped ahead of time, which makes it a great make-ahead gluten-free side dish for Thanksgiving or Christmas dinner!

Prep The Casserole Base. Cook the green beans, make the mushroom sauce, coat the beans in sauce, and spread the green bean mixture out into the baking dish as directed.
WAIT To Add The Onions. The trick is NOT adding the crispy onions until right before baking. Cover the casserole (without the onions!) and chill overnight, as needed.
Pull It Out & Bake When You’re Ready. Remove the casserole from the fridge 20-30 minutes before baking then top with onions and cover with foil to bake, as directed.

Psst! If you’re making this easy recipe in advance, you can also get a head start on other classic thanksgiving recipes, like Gluten-Free Stuffing, Sweet Potato Casserole, and Cranberry Sauce!

A plate of Gluten-Free Green Bean Casserole with homemade mushroom sauce and crispy onions

FAQ + Tips And Tricks For The Best Gluten-Free Green Bean Casserole

Can’t Find Storebought Gluten-Free Crispy Onions? Make Your Own! They can be a labor of love, but homemade french fried onions sure are delicious! We recommend this gluten-free crispy onions recipe, made with vidalia onions, buttermilk, gluten-free flour, pantry seasonings, and oil! Or, swap them out for these Gluten-Free Crispy Fried Shallots, instead!

Try Adding Cheese! Feel free to stir 1 heaping cup of sharp cheddar cheese into the green beans and sauce mixture, if you like! My mom always did during the holiday season when I was growing up, and the cheesy version of this creamy green bean casserole is delicious.

Can I Use Cornstarch Instead of Flour? Yes! You’ll just need to adjust the method slightly. Instead of sprinkling the flour on top of the mushroom mixture, stir an equal amount of cornstarch (3 TBSP) into the chicken broth and tamari before adding it to the pan.

Can I Use Canned Green Beans? You can, though the casserole will have a softer texture and slightly duller color than if you’re using frozen or fresh beans. One (15 oz) can of green beans is equal to about 1/2 pound of fresh green beans, so you’ll need about 4 cans of green beans to replace 2 pounds of fresh or frozen green beans. Make sure to drain them very well, so they don’t water down the casserole!

More Gluten-Free Thanksgiving Side Dish Recipes To Try

spoon scooping into a pan of paleo sweet potato casserole

Paleo or Vegan Sweet Potato Casserole

Orange Honey Cranberry Sauce

a pan of gluten-free stuffing with herbs

Classic Gluten-Free Stuffing

Gluten-Free Maple Cornbread

Did You Make This Recipe?

Tell me all about it! Leave a star rating below when you try our Gluten-Free Green Bean Casserole recipe. I can’t wait to hear how it goes!

Tap to Leave a Review

Gluten-Free Green Bean Casserole

All the classic flavor you love, simply made gluten-free! Our gluten-free green bean casserole recipe is made with an easy homemade sauce you'll LOVE. It's the perfect Thanksgiving side dish to try this year!

Prep Time: 20

Cook Time: 45

Total Time: 1 5

Print Pin Rate

Servings: people

Ingredients

2 pounds Frozen Cut Green Beans
4 Tablespoons Butter
8-12 oz. Mushrooms Thinly Sliced
1 clove Garlic Minced
1 teaspoon Kosher Salt
1/2 teaspoon Black Pepper
3 Tablespoons Gluten-Free Measure-For-Measure Flour
1 1/4 cup Chicken Bone Broth
1 cup Heavy Cream
1/2 cup Freshly Grated Parmesan Cheese
6 oz. Gluten-Free Crispy Fried Onions

Instructions

Preheat & Prep. To start, preheat the oven to 375 degrees F. Set out a glass or ceramic 9×13 casserole dish.
Start The Green Beans. Bring a large saucepan of water to a boil, then add green beans and cook 5-7 min or until tender with just a tiny bite left. While the beans cook, prepare an ice bath by filling a large bowl of water with ice and cold water. When the beans are finished cooking, drain them, then quickly add to the ice bath while you finish the mushroom sauce. This will stop the cooking process and help preserve their vibrant color.
Start The Mushroom Sauce. In a large skillet, melt butter over medium heat. Add the mushrooms and cook 8-10 min, or until golden brown and tender.
Build Flavor. Add minced garlic, salt, pepper, and gluten-free flour and cook 1-2 minutes until fragrant.
Thicken & Finish The Sauce. Pour chicken broth and gluten-free tamari into the skillet and stir, making sure to scrape up any browned bits from the bottom of the pan. Cook 3-5 minutes over medium heat until thickened. Turn off the heat and stir in cream and parmesan cheese. Stir until cheese is melted and the sauce is evenly blended.
Combine. Remove the green beans from the ice bath and drain well. In a large bowl (or your skillet if you have room!), combine mushroom sauce and green beans and stir to coat evenly.
Layer. Pour green bean mixture into your prepared pan and smooth into an even layer. Sprinkle the stop of the casserole with crispy onions.
Cover + Bake. Tightly cover the pan with aluminum foil and bake 20-25 minutes, or until the sauce is bubbling around the edges of the pan. Remove the foil then bake and additional 5 minutes to toast the onions. Serve warm and store leftovers in an airtight container in the fridge 3-4 days.

Notes

Can I Use Canned Green Beans? You can, though the casserole will have a softer texture and slightly duller color than if you’re using frozen or fresh beans. One (15 oz) can of green beans is equal to about 1/2 pound of fresh green beans, so you’ll need about 4 cans of green beans to replace 2 pounds of fresh or frozen green beans. Make sure to drain them very well, so they don’t water down the casserole!

Make Ahead Tips:

Prep The Casserole Base. Cook the green beans, make the mushroom sauce, coat the beans in sauce, and spread the green bean mixture out into the baking dish as directed.
WAIT To Add The Onions. The trick is NOT adding the crispy onions until right before baking. Cover the casserole (without the onions!) and chill overnight, as needed.
Pull It Out & Bake When You’re Ready. Remove the casserole from the fridge 20-30 minutes before baking then top with onions and cover with foil to bake, as directed.