Name: Lazy Slow Cooker Green Bean Casserole {without condensed soup)
Prep time: 10 min
Cook time: 300 min
Ingredients: 16 oz. frozen French style green beans; 12 oz. canned mushrooms, drained (stems and pieces work well so you don't have to cut them further); 11 oz. evaporated whole milk (I use lactose free); ½ cup sour cream (I use lactose free); ½ cup grated Parmesan cheese; 2 tbsp. corn starch; 1 tbsp. onion powder; 1 tsp Worcestershire sauce; ½ tsp salt; ¼ tsp. fresh ground black pepper; 6 oz. can French fried onions

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Slow cooker green bean casserole is the crockpot version of a holiday classic. This rendition is made without condensed soup, but with all of the flavor and creaminess you love. Great for a holiday or any day!

Looking down on a bowl of green bean casserole topped with lots of crispy onions

Green bean casserole is a holiday meal classic. It is commonly served for Thanksgiving dinner and Christmas dinner. However, this recipe is so easy to make, it can be served as a regular family dinner side dish.

Traditional versions of this recipe contain canned cream soup. Cream of mushroom soup seems to lead the pack. However, I have seen many comments from people looking to move away from canned soups.

Not that there's anything wrong with canned soup - it is delicious! But it can be higher in fat and sodium. So, I set out to see if this traditional green bean casserole could be made sans canned soup and still be delicious.

(Spoiler alert: the answer is YES!!!)

📝Shopping list

All green bean casserole ingredients with labels

To make this classic holiday side dish you will need:

French-style green beans - I have only made this with frozen beans
Mushrooms - Canned, drained
Evaporated milk - I use lactose-free for lactose intolerant members of the team.
Sour Cream - I use lactose-free, full fat here
French fried crispy onions - This decadent topping is what makes this dish really stand out!
Parmesan cheese - Grated
Onion powder
Corn starch
Worcestershire sauce
Salt & pepper

Exact quantities can be found in the recipe card below.

🥣Assembly

Stir together onion powder, corn starch, salt, pepper, milk, and drained mushrooms in a medium bowl. Microwave on high for 3 minutes or so and mix.

A white bowl with a whisk mixing ingredients

The mixture should be about as thick as a typical creamed soup. If you need to make it thicker, continue to microwave in 30-second intervals. Stir in between each interval until desired consistency is reached. Set mixture aside to allow to cool slightly.

Add beans and parmesan cheese to your slow cooker. When the creamy mixture above has cooled, add it to your slow cooker too and stir to fully combine all ingredients.

Green beans in a rectangular slow cooker being stirred together with sauce and mushoromos

Cover and cook on low for 5-6 hours

Before serving, stir sour cream into green bean mixture and top with crispy fried onions. Do NOT place the cover back onto the slow cooker once French-fried onions have been added or they will get soggy.

Keep slow cooker on warm setting with lid off for serving.

🍽Serving suggestions

This classic dish is at home next to the usual holiday offerings like turkey, mashed potato, and stuffing. However, it is also wonderful served alongside a BBQ, Pot roast, or pasta dish. There is almost no wrong time for a classic green bean casserole!

Storing leftovers

Leftovers can be stored in an airtight container or bag. It will last for 3-4 days in the refrigerator and can be easily reheated in a microwave oven.

A square white bowl filled with green bean casserole topped with crispy friend onion

Leftover green bean casserole can also be frozen for up to 6 months. If possible, freeze without topping. It will be tastiest if you add a fresh layer of crunchy onion to the top of the casserole.

😉Hints & hacks

The best part of this recipe is the crispy onion layer (in my opinion). Feel free to add more than what the recipe calls for. You can see from the pictures that I do!
This crockpot green bean casserole is great served buffet style since it can be served directly from your slow cooker.
If you prefer to serve this classic recipe in a decorative bowl, transfer it before adding onion topping.
To make this recipe vegetarian, be sure to use a vegetarian Worcestershire sauce.
I always suggest the use of a slow cooker liner for easy clean up. I like to buy mine in bulk for a cheaper per-piece price.
In the market for a new crock pot? I love mine!

More great holiday-worthy side dishes

❓FAQ

Why do I have to add the sour cream at the end?

Sour cream can curdle or separate if it cooks too long. For this reason, It is best added toward the end of the total cooking time. If you accidentally add it earlier, don't worry, it will still be fine. You will just need to stir a bit extra to recombine the sour cream and smooth out any lumps.

Why would I want to make this in a crockpot when it is faster in an oven?

There are several reasons:

Using a crockpot allows you to make this dish earlier in the day. This means less time in the kitchen while your guests are around.
If you plan to serve this dish buffet style, your slow cooker can double as a serving dish. This is the easiest way to ensure it stays warm (and will leave you one less dish to wash!).
If you are making this perfect side dish during the holiday season, oven space may be at a premium. Using your slow cooker will allow more oven space for other great holiday dinner treats.