Creamy Green Bean Mushroom Casserole
This one-pan Creamy Green Bean Mushroom Casserole takes the traditional side dish to the next level. With a light homemade, creamy sauce, tender green beans, meaty mushrooms, and crispy fried onions, it’s truly unmatched! Plus, this one secret ingredient takes this dish to the next level!
Growing up, my mom’s green bean casserole recipe was always a staple at holiday meals, served alongside classic Thanksgiving recipes like easy stuffing and cornbread pudding. I always loved it, but there’s no denying that it’s not exactly the healthiest option.
Now that I host holiday meals myself, I’ve taken the original recipe and given it a twist, making green bean casserole from scratch!
I skipped the canned cream of mushroom soup entirely. Instead, opting for a homemade garlic soy cream sauce that is a little bit lighter but still absolutely delicious.
The secret ingredient in this dish is low sodium soy sauce. The soy sauce adds a savory umami flavor that’s hard to resist, especially when combined with meaty mushrooms. Top it off with crispy fried onions, and you have the perfect side dish!
Even better, all the ingredients combine and cook in a single pan, keeping prep time minimal and cleanup a breeze. That means you’ll have plenty of time to prepare the rest of your feast!
Recipe Ingredients
- Butter – Use salted butter to soften the garlic and mushrooms and create a rich flavor base.
- Garlic – For the best taste, use whole garlic cloves and mince them yourself.
- Mushrooms – Baby Bella mushrooms add a chunky, meaty texture along with a boost of plant-based protein.
- Flour – All-purpose flour helps soak up the excess liquid from the mushrooms, preventing the dish from becoming soggy.
- Milk – 2% milk forms the base of the creamy sauce, creating a silky consistency and rich flavor.
- Low Sodium Chicken Broth – Chicken broth helps thin out the milk. If needed, vegetable broth will also work. Whichever you choose, I recommend choosing low-sodium varieties to prevent the dish from becoming overly salty!
- Low Sodium Soy Sauce – This infuses the dish with incredible salty, umami flavor. Again, low-sodium soy sauce is best. If you need this green bean mushroom casserole to be gluten-free, feel free to use tamari or coconut aminos instead.
- Green Beans – Fresh green beans are best. I don’t recommend using frozen or canned varieties, or your casserole is likely to become mushy. Wash and dry the green beans. Trim the ends and cut them in half of they are extra long.
- Kosher Salt and Black Pepper – Adjust to taste.
- Crispy Fried Onions – I use store-bought French Fried onions to keep this dish simple. However, if you have the time, you can make homemade fried onions instead.
How to Make Green Bean Mushroom Casserole with Soy Sauce
- Prepare. Before you begin, preheat your oven to 350 degrees Fahrenheit.
- Sauté. Heat a large oven-safe pan over medium-high heat. Add the butter, sliced mushrooms, and minced garlic. Cook until the butter is melted and the mushrooms soften and brown.
- Add the flour. Dust the lightly browned mushrooms with all-purpose flour, kosher salt, and black pepper. Stir to combine and soak up excess moisture.
- Create the sauce. Reduce the heat to medium. Then, slowly add the milk, stirring regularly. Next, add the low sodium chicken broth slowly. Finally, stir in the low sodium soy sauce and simmer.
- Simmer. Add the prepared green beans to the pan with the sauce. Allow the ingredients to simmer until the green beans are vibrant and tender but not mushy. (simmer in the sauce for 5 minutes if you blanched the green beans and 10 minutes if you did not.)
- Optional Step: If you want, after the green beans have simmered for 5-10 minutes, you can transfer the mixture from the pan to a 9×13-inch baking dish thats been lightly sprayed with cooking spray.
- Bake. Sprinkle the crispy fried onions evenly over the dish. Then, cover it with foil, and bake for 20 minutes. Remove the foil, and continue to bake until the top is golden brown.
- Serve. Allow your creamy green bean casserole to cool slightly in the pan, and enjoy warm!
Expert Tips
- Blanch the green beans. I like my green beans to stay fairly crisp so I typically do not blanch them first. However, if you prefer a softer texture, feel free to blanch the green beans before adding them to the dish. To do so, submerge them in water in a large pot of boiling water, and boil for 3-5 minutes. Then, drain off the excess liquid, and proceed with the recipe as normal.
- Use a casserole dish. If you don’t have an oven-safe skillet, feel free to transfer the ingredients to a 9×13-inch baking dish instead. This also makes for a pretty presentation when feeding a crowd!
- Add more mushrooms. Feel free to include extra mushrooms if desired. Just keep in mind that mushrooms hold a lot of liquid and will likely make the sauce thinner.
- Let the dish cool. Allow your casserole to cool slightly before serving, allowing the sauce to thicken!
Frequently Asked Questions
Yes, you can assemble the ingredients up to 48 hours in advance. Just combine the ingredients on the stove. Then, leave off the crispy onions, cover the dish with foil, and store it in the fridge. Bring it to room temperature, add the crispy onions, and bake as normal when you’re ready to serve.
Stored in an airtight container, leftovers will stay fresh in the refrigerator for three to four days. When you’re ready to eat, reheat individual portions in the microwave. Or, cover the dish, and warm it in the oven just until heated through.
The most common reason is not soaking up the excess liquid from the mushrooms. Make sure to toss them well with flour, and your casserole shouldn’t turn out soggy!
Other Holiday Recipes to Consider Trying
- easy homemade stuffing
- one-pan crispy smashed potatoes
- homemade cornbread pudding
- candied sweet potatoes
- easy mashed potatoes
- three ingredients Boursin cheese salami cups
Creamy Green Bean Mushroom Casserole
Equipment
- 1 large oven safe pan
- 1 9×13 inch baking dish optional
Ingredients
Garlic Soy Sauce
- ¼ cup salted butter, four tablespoons
- 24 ounces baby bella mushrooms, washed, dried and sliced
- 1 tablespoon garlic, minced about 2-3 cloves.
- 2.5 tablespoons AP flour, all purpose flour
- ¾ – 1 cup 2% milk
- ½ cup low sodium chicken broth, if the sauce gets too thick simply add a touch more broth.
- 1.5 tablespoons low sodium soy sauce
- 24 ounces fresh green beans, rinse and dry the beans. trim the ends and cut them in half if they are long.
- kosher salt, to taste
- black pepper , to taste
- ½ cup crispy fried onions
Instructions
- Preheat the oven to 350 degrees. Grab a large oven safe pan and place it over medium high heat. Add butter, sliced mushrooms and minced garlic. The mushrooms will soften and brown, releasing some moisture. Once lightly browned, dust the mushrooms with the AP flour, kosher salt and black pepper. Stir well. Allowing the flour will soak up the moisture.
- Reduce the heat to medium. Next, slowly add the milk. As you add the milk, a creamy sauce will begin to form. Once all the milk is added, add the low sodium chicken broth. Stir well. If the sauce gets too thick, simply add a touch more broth.
- Once the chicken broth is well incorporated, add the low sodium soy sauce. Stir until well combined.
- Next, add the prepared green beans to the simmering sauce and mushrooms. Simmer the green beans in the pan with sauce and mushrooms for 5 minutes if you blanched the green beans and 10 minutes if you did NOT. You do not want them to get too soft. NOTE: you have the option to blanch the green beans in a separate pot of boiling water to soften them. I prefer a slight crunch so normally I skip this step.
- Optional Step: If you want, after the green beans have simmered for 5-10 minutes, you can transfer the mixture from the pan to a 9×13-inch baking dish thats been lightly sprayed with cooking spray.
- Next, sprinkle crispy fried onions over the top of the dish. Cover the dish with foil and bake it for 20 minutes at 350 degrees. Remove the foil and bake for an additional 5 minutes. Remove from the oven and let the casserole rest for a few minutes before serving.
Notes
- Blanch the green beans. I like my green beans to stay fairly crisp so I typically do not blanch them first. However, if you prefer a softer texture, feel free to blanch the green beans before adding them to the dish. To do so, submerge them in water in a large pot of boiling water, and boil for 3-5 minutes. Then, drain off the excess liquid, and proceed with the recipe as normal.
- Use a casserole dish. If you don’t have an oven-safe skillet, feel free to transfer the ingredients to a 9×13-inch baking dish instead. This also makes for a pretty presentation when feeding a crowd!
- Add more mushrooms. Feel free to include extra mushrooms if desired. Just keep in mind that mushrooms hold a lot of liquid and will likely make the sauce thinner.
7 Comments on “Creamy Green Bean Mushroom Casserole”
This has replaced the original green bean casserole for my family. I’ve made it with fresh and frozen beans and both work great.
This sounds delicious and can’t wait to try it! Do you think that you could make this the night before and pop it in the oven the next day? Of course it would have to cook longer in the oven, but I am wondering if anyone has tried it?
I have not tried it but dont see why not. Just don’t overcook your beans! Also, I wouldn’t add the crispy onions until you’re ready to heat it. That way they don’t get soggy. Finally, if your sauce gets too tight, simply add a touch more chicken broth and stir it until it’s well combined.
What if you don’t have a cast iron skillet?
Just use an oven safe pan. Try to keep it the same size too.
Made this for Thanksgiving this year. My whole family loved it! So easy but really impressive when served. I forgot to buy the fried onions so I substituted cooked bacon for the topping. I’m going to make again soon with the fried onions.
These were so delicious as a thanksgiving side- we might have to start making them during the year! My daughter made them for us…super easy to make and comes out great!