Slow Cooker Green Bean Casserole


This post may contain affiliate links. Please read our disclosure policy.

Slow Cooker Green Bean Casserole is a staple for Thanksgiving and Christmas. My recipe follows the classic recipe but made in the slow cooker.

My family can not go without the Green Bean Casserole. It’s pretty much the best side dish for Thanksgiving or Christmas (well, besides the slow cooker mashed sweet potatoes and slow cooker stuffing).

close up of green bean casserole with a spoon in it.

This recipe for Slow Cooker Green Bean Casserole makes a ton. When I make this for Thanksgiving, it feeds about 15, with lots of leftovers. I think this recipe will serve up to 20 people.

canned green beans, cream of mushroom soup, french fried onions, milk in front of slow cooker.

How to make Green Bean Casserole in the Crock Pot:

My recipe is very close to the original green bean casserole recipe from Campbell’s but enough to feed a crowd. Though, I skip the soy sauce in my recipe.

  • Green beans – I use canned
  • 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. Be sure to see my tip on how to brown them.
  • Seasonings – Just pepper and onion powder. No salt needed, the green beans and cream of mushroom soup have PLENTY of salt added.
opened green beans, french fried onions, and cream of mushroom mixture on wooden table

How long do I cook?

  • Place the lid on the slow cooker.
  • Cook on HIGH for 2.5 hours without opening the lid during the cooking time.
3 photos of green bean casserole steps.

How can I brown the French fried onions without an oven?

  • 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.
  • Sprinkle over the green bean casserole and serve!
French fried onions in a skillet

Can I use fresh or frozen green beans instead of canned?

  • Use 10 cups fresh (trimmed and cut) or frozen green beans instead of canned.
  • Cook for 3.5 on high or until the green beans are tender.
finished cooking green bean casserole with wooden spoon in it

What other green bean sides can I make in the slow cooker?

close up image of green beans in sauce with French fried onions on top.

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 holiday side dishes we can’t live without:

Want to make more magic in your crockpot? Stay up to date and subscribe to my newsletter and follow along on Facebook, Instagram, Pinterest and YouTube.

green bean casserole in a slow cooker with wooden spoon in it.

Slow Cooker Green Bean Casserole

4.75 from 16 votes
Prep Time: 10 minutes
Cook Time: 2 hours 40 minutes
Total Time: 2 hours 50 minutes
Servings: 20
Is any holiday meal complete without the classic Green Bean Casserole? Free up oven space by using your slow cooker.


  • 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. green beans, (Ten – 14.5-oz cans; drained)
  • 12 oz. French's French Fried Onions, (Two – 6-oz canisters)
  • non-stick cooking spray


  • Spray the slow cooker with the non-stick cooking spray if desired.
  • Add the drained green beans to your slow cooker.
  • In a medium-size bowl, whisk the cream of mushrooms soup, milk, black pepper, and onion powder until smooth.
  • Pour the soup mixture over the beans. Add half (one canister) of the french friend 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).

How to Video

Sarah’s Notes

Can I use fresh (trimmed and cut) or frozen green beans?
  • 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.
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.
Can I brown the onion on top of the casserole at the end of the cooking time (instead of using a skillet to brown them.)?
If your slow cooker is oven safe (check your manual), sprinkle the remaining canister of French fried onions to the top of the casserole.
  • 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.
Can I halve this recipe?
Yes, you can cut this recipe in half. You will only need to cook for 2 hours on high before adding the remaining onions.


Calories: 201.71kcal | Carbohydrates: 24.1g | Protein: 6.06g | Fat: 10.01g | Saturated Fat: 4.3g | Cholesterol: 2.9mg | Sodium: 480.77mg | Potassium: 499.33mg | Fiber: 5.64g | Sugar: 7.01g | Vitamin A: 1428.07IU | Vitamin C: 25.07mg | Calcium: 84.77mg | Iron: 2.44mg

Nutrition info is auto-generated. This information is an estimate; if you are on a special diet, please use your own calculations.

Made this recipe? Leave a comment below!

Other recipes you may like

Leave a comment

Your email address will not be published. Required fields are marked *

Recipe Rating


  1. Terry says:

    Can I make this the day before and refrigerate?

    1. Sarah Olson says:

      Yes, that should do fine.

  2. Janice says:

    5 stars
    I strongly advise against using fresh green beans for this recipe. I’ve made it, using canned green beans, for Thanksgiving 2021 and Thanksgiving 2022, and it was delicious and got rave reviews. This year, I decided to use fresh green beans instead of canned. Big misake. The green beans were undercooked, even after three hours in the crock pot, and the entire casserole was too soupy. I have no idea why using fresh green beans in place of canned made the casserole too soupy, but it did. I’m giving the recipe 5 stars because it’s delicious if made with canned green beans, and plan to redeem myself for 2023 by making it with canned beans for Christmas.



    1. Sarah Olson says:

      You could cut this in half and then freeze the other half for an other meal.

  4. Anonymous says:

    Only 1/2 cup of milk? Doesn’t seem like enough

    1. Sarah Olson says:

      Yes, the soup alone is almost the right consistency.

    2. Cindy says:

      5 stars
      Yes, I agree. I added one-half cup more milk and I plan to add even more than that next time.

      This recipe is amazing, though. My family LOVES it

  5. Lois McKnight says:

    Do you have to brown the 2nd can of French fried onions that you add before serving?

    1. Sarah Olson says:

      You don’t have to brown them but they taste better if you do. I brown them in a dry skillet or in a bowl in the oven.

  6. Susan says:

    How long would I cook this on low? I need to be gone for about 4 hours and it would be overcooked. Thank you!

    1. Sarah Olson says:

      4 hours on low would work great.

  7. Nancy says:

    I need more than this makes but I don’t want to double. I have an 8qt slow cooker. I was going to adjust and add about 1/3 more of everything to make sure it fits in my cooker. Do I need to add additional time that it cooks? How much?

    1. Sarah Olson says:

      It won’t need much more time, probably just 30 minutes. It’s all mostly cooked, room temperature items.

  8. Laura says:

    Sounds great but what is the serving size? As a diabetic i need to know that for the carb count.
    I see the grams listed but not the serving size.

    1. Sarah Olson says:

      Hi, I do not have serving sizes, I apologize.

  9. Kat L. says:

    I plan to make this for Thanksgiving dinner. 20 servings is too much. Could I half the recipe and cook it in a casserole shaped crockpot? Is it necessary to half each ingredient exactly?
    Kat L.

    1. Sarah Olson says:

      I would try to stick to half of the recipes closely so you don’t end up with too dry or too wet green bean casserole.