This modern green bean casserole recipe is a casserole in name only. We deconstructed and elevated the traditional Thanksgiving side dish to use fresh green beans, and a creamy homemade mushroom sauce, and topped it with homemade gluten-free fried onions for a modern take.

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You may be wondering why go to the trouble of updating a much-loved classic side dish? And while we love a traditional green bean casserole, I needed something that was easy to make ahead of time and better suited for a small group.
Plus I wanted to make this without canned cream of mushroom soup.
This deconstructed side dish pairs perfectly with our not-too-sweet roasted cranberries, a side of small-batch mashed potatoes, and gluten-free turkey gravy.
But most importantly, it is a recipe I can serve all year round. Not just on holidays.
Green beans and mushrooms pair perfectly with our blackened cod and with our braised pork roast.
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📖Why This Recipe Works
Like any gluten-free green bean casserole recipe, we had to eliminate or find alternatives for the gluten-containing ingredients. Namely, the cream of mushroom soup, soy sauce, and french fried onions.
The base of this recipe is roasted fresh green beans. Which is then topped with a creamy mushroom cheese sauce and finished with crispy fried onions (which are actually baked not fried!).
🧾 Ingredient Notes
This recipe as had three components, here is a brief look at the ingredients and substitutions for each part.
Roasted Green Bean Ingredients
- Fresh green beans- a traditional green bean is what I use. Haricot vert, French beans, don't stand up as well to the roasting.
- Olive oil
- Kosher salt
Creamy Mushroom Sauce
- Cremini mushrooms- You can use any mushroom you like, including rehydrated wild mushroom mixes for even more flavor!
- Olive oil
- Garlic
- Dry white wine - Use a sauvignon blanc or something similar. You can also substitute chicken or vegetable broth.
- Fresh thyme
- Pecorino- I use a pecorino romano cheese. You can substitute grated parmesan just make sure it is fresh.
- Heavy cream
- Kosher salt and pepper
Gluten-Free French Fried Onions
- White onions
- Buttermilk
- Olive oil divided
- White rice flour
- Cornmeal
- Kosher salt
- Garlic powder
Want to use store-bought onions? No problem we have a list of the best store-bought fried onions that are gluten-free. You can also substitute slivered almonds if you aren't an onion fan.
See the recipe card for quantities.
⏲️ How to Make Roasted Green Bean Casserole
I am not going into the details on the gluten-free french fried onions as we have a post that details all that out for you. But we did include the full instructions in the recipe card below.
Mushroom Cream Sauce
First, we are going to saute the mushrooms to a golden brown. Heat your oil in a saute pan over medium heat. Add the mushrooms until they release their moisture. Continue cooking until the liquid total evaporates.
Add your garlic and stir for another 30 seconds to 1 minute. Deglaze the pan by adding the wine sauce and then simmer until the liquid reduces by half.
Stir in heavy cream and bring to a simmer. Do not boil. Reduce the heat to low and whisk in the cheese.
Continue whisking until no lumps remain and the sauce thickens to the point it coats a spoon.
Stir in thyme leaves and taste for salt and pepper. If using pecorino cheese I typically won't salt the sauce.
Roasting the Green Beans
Preheat your oven to 400 F degrees.
Place the green beans on a sheet pan and drizzle with olive oil and sprinkle with salt and toss to coat.
Bake the green beans until tender and the skins blister, 8 to 10 minutes depending on the thickness of the green beans.
Assemble and Serve
To serve, transfer the roasted green beans to a platter. Drizzle over creamy mushroom sauce and top with the fried onions.
💭 Green Beans and Truffle Variation
This is officially the fanciest version of green bean casserole ever! It is big on mushroom flavor.
You will need:
- Truffle oil
- ½ ounce of dried wild mushrooms
First, grind up your dried mushroom in a spice grinder. Nope, we are not going to rehydrate them. Instead, we use them in our cream sauce as a thickener just like in our mushrooms and roasted chestnuts recipe.
Make your roasted green beans and fried onions as normal.
For the cream sauce, cook as normal through the step of adding the cream. Add half of the normal amount of cheese (now just a ¼ cup) and dried mushroom powder. Cook until thick.
Remove the pan from the heat and stir in 1 to 2 teaspoons of truffle oil. Truffle oil varies in intensity from brand to brand so start off with 1 teaspoon and season to taste.
Assemble and serve as normal.
🌡️ Making Ahead and Storage
Gluten-free fried onions can be made up to 2 days ahead and stored in a sealed container at room temperature. Lightly toast on a dry baking sheet to crisp back up before serving.
The mushroom cream sauce can be made up to 2 days in advance. Store in an airtight container in the fridge. Reheat over low heat in a small saucepan. DO NOT BOIL!
When making this for a holiday, here is my strategy for making our dish ahead of time and assembling it the day of:
- 2 days before the holiday I make the french fried onions and the mushroom cream sauce. Store according to the notes above.
- 1 day before I wash and trim my green beans.
- While the turkey is roasting, toss the green beans in olive oil and salt. Spread out on the sheet pan in a single layer.
- Spread the onions on a dry sheet pan. They can go in with the turkey or the green beans. Cook for 10 minutes until they toast back up. Set aside until needed.
- 10 to 15 minutes before the meat is done, pour the cream sauce into a small saucepan. Reheat over low, stirring occasionally.
- When the turkey comes out of the oven, increase the heat to 400 F degrees. The oven should take 5 minutes or so.
- Roast the green beans for 8 to 10 minutes. Assemble as normal
🦃More Easy Recipes for Thanksgiving
💬Frequently Asked Questions
Scoop out the mushrooms and set them aside. In a small pan, reduce ½ cup of heavy cream and reduce it down to ⅓ of its original volume over very low heat. Slowly drizzle in the curdled sauce while whisking vigorously. Add the mushrooms back in.
No, well at least not most brands. This is why we make our mushroom cream sauce from scratch. The cheese thickens the sauce without a roux.
Did You Enjoy Making This Recipe? Please rate this recipe with ⭐⭐⭐⭐⭐ or leave a comment. It helps other wonderful people connect with our food.
📖 Recipe
Modern Green Bean Casserole
Equipment
Ingredients
- 1 pound green beans trimmed
- 2 tablespoons olive oil
- ¼ teaspoon kosher salt
Creamy Parmesan Mushroom Sauce
- 12 ounces cremini mushrooms
- 1 tablespoon olive oil
- 3 cloves garlic finely minced
- ⅓ cup dry white wine or sub chicken stock
- 2 tablespoons fresh thyme leaves
- ½ cup grated pecorino or sub grated parmesan
- 1 cup heavy cream
- kosher salt and pepper
Gluten Free French Fried Onions
- 1 white onion halved and cut into thin strips
- 1 cup buttermilk
- 2 tablespoons olive oil divided
- ¼ cup rice flour
- ¼ cup cornmeal
- ½ teaspoon salt
- ¼ teaspoon garlic powder
Instructions
- Preheat oven to 400 F degrees. Place the green beans on a sheet pan and drizzle with olive oil and sprinkle with salt and toss to coat. Roast the green beans until tender and the skins blister, 8 to 10 minutes depending on the thickness of the green beans.1 pound green beans, 2 tablespoons olive oil, ¼ teaspoon kosher salt
- To serve, transfer green beans to a platter. Drizzle over creamy mushroom sauce and top with fried onions.
Creamy Parmesan Mushroom Sauce
- In a pan, heat oil and sauté the mushrooms until they are golden brown. Add the garlic and sauté for another minute.12 ounces cremini mushrooms, 1 tablespoon olive oil, 3 cloves garlic
- Deglaze the pan with the wine, bring to a boil. Then reduce the heat and simmer until reduced by half.⅓ cup dry white wine
- Stir in heavy cream and bring back to a simmer. Do not boil. Reduce the heat to low and whisk in the cheese. Simmer until thickened slightly, 2 to 3 minutes. Stir in thyme leaves and taste for salt and pepper.2 tablespoons fresh thyme leaves, ½ cup grated pecorino, 1 cup heavy cream, kosher salt and pepper
Gluten Free French Fried Onions
- Preheat oven to 425 F degrees. Brush half the oil on a baking sheet.
- Soak onions in buttermilk for 10 minutes.1 white onion, 1 cup buttermilk
- While the onions soak, mix rice flour, cornmeal, salt and garlic powder together in a large plastic freezer bag.¼ cup rice flour, ¼ cup cornmeal, ½ teaspoon salt, ¼ teaspoon garlic powder
- Drain onion and add to freezer bag. Toss onion in flour mixture until coated.
- Spread onion mixture onto the prepared baking sheet. Drizzle remaining oil over onion. Bake in the preheated oven, tossing onions occasionally, until crisped and golden, about 30 minutes.2 tablespoons olive oil
Notes
- Gluten-free fried onions can be made up to 2 days ahead and stored in a sealed container at room temperature. Lightly toast on a dry baking sheet to crisp back up before serving.
- The mushroom cream sauce can be made up to 2 days in advance. Store in an airtight container in the fridge. Reheat in a saucepan over very low heat.
- This recipe serves 4 as the main side dish or 6 when served with multiple side dishes (i.e. Thanksgiving).
Gina says
This is definitely a green bean casserole I'd eat! None of those processed food ingredients - super fresh and tasty!
Michelle says
Looks so fresh! I love this healthier take.
Toni says
It is seriously amazing! Such a perfect side dish for people in gluten-free diet!
Jen says
Thanks so much!
Dannii says
This looks like such an amazing way to serve green beans. I love the sound of the onions on it.
Sisley White - Sew White says
This look absolutely fabulous. Can you add a touch of chilli to it, to add some spice?
Jen says
Absolutely. I would add cayenne to the cornmeal for the onions and/or crushed red pepper to the cream sauce.
Susan C says
The mushroom sauce is amazing! Don’t salt the green beans too much as the sauce and French fried onions make up for it . My green beans took around 30 minutes to come to the right texture. The French fried onions didn’t brown up like I expected, but they were still good.
Jen says
Thanks for the review. We are obsessed with the sauce.