Crockpot Green Bean Casserole is one of our favorite holiday side dish shortcuts because it frees up oven space and still gives you that creamy, classic flavor everyone loves. Frozen green beans, cream of mushroom soup, parmesan, and French-fried onions cook together until warm and delicious, then more crispy onions go on top before serving.
We love making this for Thanksgiving, Christmas, potlucks, and big family dinners when every oven rack is already spoken for. It’s simple, dependable, and such an easy way to keep a favorite side dish warm until dinner is ready.
For more favorite sides, check out our Dinner Rolls, Funeral Potatoes, Mashed Potatoes and Green Bean Casserole.
Why we think you’ll love it:
- Easy! This easy side dish is as simple as dumping in the ingredients, and letting it do its thing.
- Frees up oven space. It allows more room in the oven for baking other items – perfect for holidays!
- Frozen green beans keep it easy. No trimming or blanching needed, just add them right to the slow cooker.
- Onions go in and on top. Stirring some in adds flavor while the final topping gives that classic crunch.
Crockpot Green Bean Casserole Ingredients
- Frozen green beans (2 packages, 16 ounces each): We use frozen beans because they hold their shape in the slow cooker, giving you tender, not mushy, bites in every scoop. You can also use an equal amount of fresh green beans or 3 (14.5-ounce) cans of green beans, drained.
- Cream of mushroom soup (2 cans, 10.75 ounces each): The creamy base that binds it all together and brings the savory mushroom flavor. Try Cream of Celery soup, Cream of Chicken soup, or one of my favorites, Cream of Chicken & Mushroom soup.
- Milk (⅔ cup): Loosens the soup so it turns silky as it heats, helping the sauce coat the beans evenly.
- Grated parmesan cheese (½ cup): Adds salty, nutty depth and a little richness without making the sauce heavy. We also like to switch it up by using another favorite likeMozzarella.
- Salt (½ teaspoon): Seasons the beans and balances the creamy elements so flavors pop.
- Black Pepper (¼ teaspoon): Rounds out the savory profile.
- French-fried onions (16 ounces): Half goes inside for texture, the rest finishes the top for that signature crunch.
- optional topping: Add crumbled baconor shredded cheddar cheese to the top.
How to Make Crockpot Green Bean Casserole
COMBINE. Add green beans to the crock pot. In a medium bowl, mix the cream of mushroom soup, milk, parmesan cheese, salt, and pepper.
- Pour the soup mixture over the green beans and stir to combine. Stir in 8 ounces of the French-fried onions.
COOK. Cover and cook on LOW heat for 4 hours. Just before serving, sprinkle with the remaining 8 ounces of French fried onions.
CRISPY TOP. Preheat the oven to 350°F. Spread half of the fried onions on a baking pan and bake for 5 min. Sprinkle the onions on top of the casserole when it’s done cooking.
After cooking, this casserole can be left in the slow cooker on warm for up to 2 hours!
Kristyn’s Recipe Tips
- Use frozen green beans for the best texture in the slow cooker, they hold up better than canned and cook evenly.
- Try swapping one can of cream of mushroom for cream of chicken, it adds a cozy, savory note without extra effort.
- Warm your crock pot while you mix the ingredients, it helps the casserole reach temperature faster and stay creamy.
- Make ahead tip, assemble without the onions, cover and refrigerate, then cook in the crock pot and add onions at the end. Leftovers keep in the fridge up to 3 days.
Crockpot Green Bean Casserole Recipe
Video
Ingredients
- 2 (16-ounce) packages frozen green beans
- 2 (10.75-ounce) cans cream of mushroom soup
- ⅔ cup milk
- ½ cup grated parmesan cheese
- ½ teaspoon salt
- ¼ teaspoon pepper
- 16 ounces French-fried onions, divided
Instructions
- Add the green beans to the crock pot. In a medium bowl, mix the cream of mushroom soup, milk, parmesan cheese, salt, and pepper. Pour the soup mixture over the green beans and stir to combine. Stir in half of the French fried onions.
- Cover and cook on low heat for 4 hours. Just before serving, sprinkle with the remaining French fried onions.
Notes
- Use frozen green beans for the best texture in the slow cooker, they hold up better than canned and cook evenly.
- Try swapping one can of cream of mushroom for cream of chicken, it adds a cozy, savory note without extra effort.
- Warm your crock pot while you mix the ingredients, it helps the casserole reach temperature faster and stay creamy.
- Make ahead tip, assemble without the onions, cover and refrigerate, then cook in the crock pot and add onions at the end. Leftovers keep in the fridge up to 3 days.
- Reheat in the microwave or oven. To crisp up the French fried onions, place the leftovers under the broiler for a couple of minutes.
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
Recipe FAQ
Preheat the crockpot while gathering the ingredients.
Temperature. LOW heat is about 200°F. One hour on HIGH equals about two hours on low.
Use the right size crock pot. The beans should fill the pot between ½ and ¾ of the way.
Avoid removing the lid. It takes 20 minutes for the pot to return to the set temperature.
Drain excess liquid, if possible.
Remove the lid of the crock pot after cooking to let liquid evaporate.
Add extra French fried onions to help soak up liquid.
Prep this casserole ahead of time leaving off the onions. Cover the casserole and refrigerate. When you’re ready, heat the casserole in the crock pot, and add the onions as directed in the recipe.
Store leftover casserole in an airtight container in the fridge for up to 3 days. Reheat in the microwave or oven. To crisp up the French-fried onions, place the leftovers under the broiler for a couple of minutes.
Complete The Meal
Main Dish
Roast Turkey
3 hrs 20 mins
Roast Chicken Recipe
1 hr 30 mins
Crockpot Ham
3 hrs 40 mins
Crock Pot Pot Roast
7 hrs 5 mins
More Veggies
Creamed Corn Recipe
20 mins
Brown Sugar Glazed Carrots
20 mins
Candied Sweet Potatoes
18 mins
Oven Roasted Vegetables
35 mins
More Collections
This recipe was originally published November 2020.
This recipe is listed in the post as “Sweet Potato Green Beans Casserole.” Nothing wrong with the recipe itself, but I’m not sure why it was given that name.
I reviewed the post and don’t see a mention of sweet potatoes which is good since there aren’t any in the recipe.
Just curious..to avoid “mushiness” do you thaw out/dry the frozen beans beforehand & how many does this recipe feed?
You don’t have to, but you definitely can thaw the frozen beans if you are worried about it being mushy. You can remove the lid of the crock pot after cooking to let liquid evaporate, which may also help. And adding extra French fried onions at the end can also help soak up liquid (there are instructions in the recipe on how to do that). As far as how many it feeds, I’d say it yields about 12 servings.
I love your recipes! We just made your Fresh Green Bean Casserole last weekend for a Friendsgiving event and it was a hit! I am planning to make this recipe for Thanksgiving to free up oven space. Can you tell me what size Crock Pot you used for this? Thanks in advance!
Oh thank you so much! I’m glad the casserole was a hit. Either a 5 or 6 quart crock pot would work great for this recipe!
Made this for Thanksgiving. Was so easy to make and tasted delicious.
We love green bean casserole and I love having a way to cook it in the crock pot! I was able to step away from using cans of green beans.
This was delish! My dad even liked it better than the traditional oven baked green bean casserole. Not to mention it made a lot!
Woohoo!! Glad to hear that!! Thank you so much!
Some crockpot recipes call for frozen green bean some canned. I feel like this would make a big difference. Any advice on this?
I use frozen, but honestly, both work. Can’t tell 🙂
Did you slightly boil the frozen green beans first before adding to the mixture?
You totally saved my stress level for the holidays! Not having to make this in the oven and freeing up that space is such a life saver. Wouldn’t be the holidays without this casserole.
I always run out of oven space during the holiday cooking, so making use of my slow cooker is such a helpful idea. Thank you for sharing!
This is a family tradition for us but I need oven space! So happy to have a crock pot recipe of it.