This 3-ingredient green bean casserole is the kind of simple holiday side dish that earns a permanent place on the table. It leans on a classic combination of green beans, cream of mushroom soup, and crispy fried onions for that cozy, familiar flavor so many families grew up with, and it comes together fast with almost no prep. When you need something dependable, budget-friendly, and crowd-pleasing, this little casserole really shines.

Serve this casserole alongside turkey, ham, roast chicken, or even a simple weeknight meatloaf. It also fits right in with mashed potatoes, stuffing, cranberry sauce, or buttery dinner rolls, and if you are building a holiday spread, it balances richer mains beautifully with its creamy texture and crisp onion topping.

3-Ingredient Green Bean Casserole

Servings: 6 to 8

Finished green bean casserole with crispy onions
Finished green bean casserole with crispy onions

Ingredients

2 cans cut green beans, drained, 14.5 ounces each

1 can condensed cream of mushroom soup, 10.5 ounces
1 1/3 cups crispy fried onions, divided

Directions

1. Preheat the oven to 350°F and lightly grease a small casserole dish or 8-inch square baking dish.

2. In a mixing bowl, stir together the drained green beans, cream of mushroom soup, and about 1 cup of the crispy fried onions until everything is evenly coated.

3. Spread the mixture into the prepared baking dish in an even layer.

4. Bake for 25 minutes, then carefully remove the dish from the oven and sprinkle the remaining fried onions evenly over the top.

5. Return the casserole to the oven and bake for 5 more minutes, until the onions are golden and crisp. Let it rest for a few minutes before serving.

Variations & Tips

For extra creaminess: If you like a softer, creamier casserole, add a splash of milk to the soup before mixing. This helps loosen the sauce a bit and makes it easier to coat every green bean.

For picky eaters: If someone at your table is unsure about too much crunchy topping, stir most of the onions into the casserole and leave just a light sprinkle on top. You still get that classic flavor without an overly crisp finish.

Using frozen or fresh beans: Frozen green beans work well if thawed first, and fresh green beans can be used too if they are trimmed and briefly cooked until just tender before mixing with the soup.

Make-ahead tip: Assemble the casserole a few hours ahead and refrigerate it without the final onion topping. Add the last handful of onions right before the final bake so they stay crisp.

Easy flavor boost: A little black pepper or a pinch of garlic powder can be added if you want a bit more seasoning, while still keeping the recipe simple and family-friendly.