Slow Cooker Green Bean Casserole is the simplest, most reliable way to make a classic Thanksgiving or holiday side dish. This version works with canned, fresh, or thawed frozen green beans and keeps the prep easy so you can focus on the rest of the meal.
I first shared this recipe in November 2016 and the method remains the same; the instructions here are clarified and the photos updated. This recipe leans toward the classic casserole style using cream soup and canned beans for convenience, but you can easily switch to fresh or homemade components if you prefer a from-scratch dish.
Slow Cooker Green Bean Casserole
This recipe produces a creamy, flavorful casserole with minimal fuss. Combine the creamy base and seasonings in the slow cooker, stir in the green beans and half of the crispy onions, then cook on low until heated through. Finish by topping with the remaining fried onions and letting them crisp for the final 30–60 minutes. The crockpot method frees up oven space and keeps the casserole warm for serving.
Recipe Tips
- Plan your timing: allow about 2 hours on low in the slow cooker, plus an additional 30 to 60 minutes after you add the remaining fried onions so they have a chance to crisp up.
- Make-ahead friendly: mix the casserole ingredients (except the final topping) in a bowl, cover, and refrigerate up to 3 days. When ready, transfer to the slow cooker and follow the cooking steps.
- Green bean options: canned green beans are convenient and work well. If using fresh or frozen, use about 24 ounces (1.5 pounds) total and thaw frozen beans before adding to avoid excess water in the casserole.
- Soup alternatives: if you prefer not to use cream of mushroom soup, cream of chicken or condensed cheese soup are good substitutes and will slightly change the flavor profile.
- Cheese is optional: shredded cheddar and a bit of Parmesan add richness and depth, but the casserole is fine without cheese if you want a more traditional texture.
- Keep warm: after cooking, the casserole can be left on the slow cooker’s warm setting for up to 2 hours without losing quality.
Slow Cooker Green Bean Casserole
By Nichole
Ingredients
- 4 (14.5 ounce) cans green beans, drained (or 24 oz fresh/thawed frozen)
- 2 (10.5 ounce) cans cream of mushroom soup (or cream of chicken/cheddar)
- 1/3 cup sour cream
- 3/4 cup milk
- 1/2 teaspoon salt
- 1/2 teaspoon pepper
- 1/2 teaspoon garlic powder
- 1/2 cup shredded cheddar cheese (optional)
- 1/4 cup shredded Parmesan cheese (optional)
- 1 (6 ounce) can French fried onions, divided
Instructions
- In the slow cooker, whisk together the cream of mushroom soup, sour cream, milk, salt, pepper, and garlic powder until smooth.
- Stir in the drained green beans, shredded cheddar, Parmesan, and half of the French fried onions. Spread everything evenly in the crockpot.
- Cover and cook on low for 2 hours. After 2 hours, stir the casserole to distribute heat and flavors evenly.
- Top with the remaining French fried onions, replace the lid, and cook an additional 30 minutes to 1 hour to allow the topping to crisp and the casserole to finish cooking.
- Serve warm straight from the slow cooker or transfer to a serving dish. Leftovers keep well in the refrigerator for a few days.
Notes
- The cheese in this recipe is optional. Leaving it out does not require any other changes to the recipe.
- MAKE AHEAD: Mix the casserole in a bowl, cover, and store in the refrigerator for up to 3 days before transferring to the slow cooker.
- After cooking, the casserole can be held on the slow cooker’s warm setting for up to 2 hours.
- If using fresh or frozen green beans, aim for a total of about 24 ounces (1.5 pounds); thaw frozen beans first to prevent excess liquid.
Nutrition
Serving: 1.5 cup. Calories: approximately 150 kcal. Nutrition information is an approximation and will vary depending on brands and ingredient choices.
Additional Info
Course: Side Dish. Cuisine: American. Serves: about 10.
Enjoy this easy crockpot green bean casserole at your next holiday gathering. It delivers classic flavor with minimal effort, freeing up your oven and helping you focus on other dishes and guests.
~Nichole