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Slow Cooker Green Bean Casserole is a staple for the holidays! My version has everything creamy and decadent you expect and enough to feed the masses.

Featured Comment
Thank you for this! I am not a cook and have to bring something to a work potluck luncheon next week. This is one of my favorite holiday sides and works out great to be able to prepare and then keep it plugged in once at work.
– paula
Everyone has their favorite holiday side dish, and ours is slow cooker green bean casserole. My no-oven version is made with canned beans (what my family grew up on), it gets rave reviews. This recipe feeds about 20 (or less people and enough for leftovers). We make this casserole for Thanksgiving AND Christmas.
My recipe is very close to the original green bean casserole recipe from Campbell’s but enough to feed everyone. Though, I skip the soy sauce in my recipe.

Key Ingredients
Green beans – I used canned but there are substitutes below
Cream of mushroom soup – 3 cans in this recipe, this makes for a very saucy casserole
Milk – This helps thin out the soup
French Fried Onions – These are what make the dish, they add crunch and oniony flavor.
Seasonings – Just pepper and onion powder. No salt needed, the green beans and cream of mushroom soup have PLENTY of salt added.

How to make Green Bean Casserole in the Crock Pot
- Mix all the ingredients except half of the onions in a large bowl or right in the crockpot.
- Cook until hot and bubbly.
- Top with browned onions and serve.

Can I use fresh or frozen green beans instead of canned?
If you prefer fresh or frozen, you can use that instead, simply measure out 10 cups and cook the casserole for 3.5 hours on high or until the green beans are tender.
How can I brown the French fried onions?
Short on oven space or without one? Place the onions in a dry skillet set to medium-high heat on the stove-top. Use a spoon and stir around the onions, for about 3 minutes or until browned.

My Tips for the Best Green Bean Casserole
- Type of Beans: Use CUT GREEN beans NOT French Green beans for casserole that isn’t watery or mushy.
- Better Flavor: Rinse your green beans well, they will taste less tinny. I do this right in the can; drain the bean liquid, add water to the can and drain again by using the lid to hold the green beans in the can (drain well).
- Don’t Squash: Fold everything together gently. You don’t want to mash up those whole green beans.
- Toasty: Don’t skip on browning the onions for topping, they can taste stale if you don’t.

Variations:
Cheesy: Add 2 cups shredded sharp cheddar cheese to the mix – SO GOOD!
Bacon: Cook up one pound of bacon and crumble into your casserole.
Soup Swap: Not everyone likes cream of mushroom; you can use cream of chicken, cream of celery, cream of onion or even cream of bacon!
Onion Swap: Instead of French Fried Onions, try adding cooked onion rings on top! You can find them near the frozen fries at the store.

Complete Your Holiday Meal
Holiday Sides:
Round out your plate with Slow Cooker Candied Yams, Slow Cooker Cranberry Sauce, and Slow Cooker Mashed Sweet Potatoes for a touch of sweetness and color.
Comforting Veggies:
Slow Cooker Mashed Potatoes, Slow Cooker Acorn Squash, Slow Cooker Butternut Squash, and Brown Sugar Carrots add cozy, comforting flavors to any holiday meal.
Classic Stuffing Options:
Slow Cooker Stuffing and Slow Cooker Stove Top Stuffing keep things simple while delivering that traditional savory stuffing flavor everyone expects.
Main Dish Favorites:
Serve alongside Slow Cooker Turkey Breast, Holiday Ham, or Crockpot Spiral Ham to create a full holiday spread with almost no effort.

Slow Cooker Green Bean Casserole Recipe
How to Video
Equipment
Ingredients
- 31.5 oz. cream of mushroom soup, (three – 10.5 oz cans)
- 1/2 cup milk
- 1/8 tsp black pepper
- 1/8 tsp onion powder
- 145 oz. canned cut green beans, (Ten – 14.5-oz cans; drained)
- 12 oz. French's French Fried Onions, (Two – 6-oz canisters)
- non-stick cooking spray
Instructions
- Spray the slow cooker with the non-stick cooking spray if desired.
- Add the drained green beans to the slow cooker. In a medium bowl, whisk the cream of mushroom soup, milk, pepper, and onion powder until smooth, then pour the mixture over the beans.
- Add half (one canister) of the French Fried Onions. Stir gently.
- Place the lid and cook on HIGH for 2½ hours.
- Brown the remaining canister of French fried onions in a skillet on the stove top. Set the skillet to medium high heat, stir the onions around until brown (about 3 minutes).
- Sprinkle the onions over and serve. (If you are traveling, you can brown your onions at home then add them to the slow cooker right before serving).
Sarah’s Notes
- Use 10 cups fresh (trimmed and cut) or frozen green beans instead of canned.
- Cook for 3.5 hours on high or until the green beans are tender.
- Remove the slow cooker insert from the heating element and place it in the oven WITHOUT the lid.
- Cook for 10 minutes at 350°F or until the onions are browned.
- OR place the onions in a small dish in the oven for 10 minutes or until browned, then sprinkle over the casserole.
Nutrition
Nutrition info is auto-generated. This information is an estimate; if you are on a special diet, please use your own calculations.
How long can I keep this on the warm setting after cooking?
You can keep this on the warm setting for 3 hours. Though keep an eye on it and make sure the edges aren’t scorching, stir or turn off if the edges are getting too hot.
More Green Bean Sides to Choose from
If you’re looking for different green bean sides to round out your meal, try Slow Cooker Cheesy Green Bean Casserole, Slow Cooker Green Beans and Bacon, Slow Cooker Green Beans and Potatoes, or Bacon Green Bean Casserole.


















I wanted you to know I made this for an office potluck last week. It was so easy and was a big hit. We only have two microwaves in our office, so this was an ideal solution to keep the food warm. Thank you for sharing this recipe.
P.S. Most of the women in my office thought my wife made this dish 🙂
I’m so happy to hear that Bob! 🙂 Thanks for letting me know who it worked for you.
Silly question…do you really use 10 cans of green beans or is that a typo?! Thanks, can’t wait to try this!
Yes 10! It serves 20, but this could easily be cut in half if you aren’t serving so many. 🙂
Thank you VERY MUCH for including the size of the slow cooker in your recipe. We have a gazillion of them to choose from so this is a HUGE help.
If you use frozen green beans from a bag do you need to increase the cooking time because the quantity is a lot larger in this recipe than in the video someone posted a link to? Thanks
I have never used frozen. But I would assume it would take much longer to cook since they are frozen and raw. I think the video said 5 hours on Low? That might be right even if you used a more than the video used.
When I use frozen I Cooke them up a bit and then I use them…. It turns out great for the oven and should work well with this.. It only takes a few minutes:-)
I am making this for a holiday party and won’t have an oven available, will the onions cook on top in the crockpot or should I leave them out?
What if you browned them at home on a sheet tray and brought them to sprinkle on top. The crock pot won’t help those onions, it may make them soggy if they aren’t browned.
Great idea using the slow cooker! I have gluten free in my crowd so I plan on cooking the onion rings in my toaster oven and serving on the side. Everyone happy :0)
The “cream of” soups have gluten in them what do you use instead?
Progresso makes a gluten free cream of mushroom soup or you can make your own. I’m using the progresso one!
Janet, just a reminder, cream of mushroom soup has gluten in it.
Can I transfer the casserole to a different serving platter before putting in the oven?
Yes that would work fine. 🙂
I want to use frozen cut green beans. Do I need to cook them first? If so, how long?
I had same question, thought yes just dump them in but Googled to be sure..yep, here’s a video….http://allrecipes.com/video/5229/slow-cooker-green-bean-casserole/
What other soup can you use instead of the cream of mushrooms?
Cream of celery or cream of chicken would work too.
Cream of onion too!
Would french cut green beans work instead of the cut green beans?
I don’t see why not! Just drain them very well. 🙂