This southern green bean casserole skips the cans entirely, using fresh green beans, sauteed mushrooms, a quick milk based sauce, and homemade crispy onions fried right in your skillet.
It serves eight, fills a 13×9 dish, and takes about 70 minutes from start to finish. The sauce is creamy and savory, the beans stay tender, and the golden onions on top are the part everyone reaches for first.
Table of Contents
Why This Southern Green Bean Casserole Recipe Works
The sauce is built the old way. Mushrooms and onion cook in butter until soft, then milk thickened with cornstarch goes in and simmers until it coats a spoon. A little low sodium soy sauce adds the deep savory flavor that canned soup usually provides, without the extra sodium.
Homemade fried onions change everything. Thin onion strips tossed in flour and fried in hot oil turn crisp and sweet, and they stay crunchier than store bought ones because they go on just before serving.
Boiling the beans until fork tender is the southern way. It gives the dish a soft, comforting texture that soaks up the sauce, and it means no one is chasing squeaky beans around the plate.
Ingredients for Southern Green Bean Casserole
- 8 cups fresh green beans, trimmed and cut into 1 inch pieces (frozen works too)
- 2 tablespoons unsalted butter
- 8 oz white mushrooms, sliced
- 1 small yellow or Vidalia onion, cut into thin strips and divided
- 2 cups whole milk
- 2 tablespoons cornstarch
- 2 tablespoons low sodium soy sauce
- 1/4 teaspoon salt
- 1/4 teaspoon black pepper
- 1 cup all purpose flour
- 1 1/2 cups neutral oil for frying
Green beans. Fresh beans give the ideal texture. Boil them until fork tender so they are soft enough to absorb the sauce.
Mushrooms and onion. Half the onion cooks into the sauce with the mushrooms for sweetness, and the other half becomes the crispy topping.
Milk and cornstarch. Whisk the cornstarch into cold milk before it hits the pan so the sauce thickens smoothly without lumps.
Low sodium soy sauce. Two tablespoons add savory depth. Because soy sauce is salty, only a quarter teaspoon of salt is needed.
Flour and oil. The flour coats the onion strips for a crisp crust, and the oil should sit near 350 degrees F so they fry without turning greasy.
How to Make Southern Green Bean Casserole
1. Heat the oven. Heat the oven to 350 degrees F and grease a 13×9 inch baking dish.
2. Boil the beans. Cover the beans with water in a large saucepan, bring to a boil over high heat, then reduce to medium low and cook about 15 minutes, until fork tender. Drain well and spread them in the baking dish.
3. Cook the mushrooms. Melt the butter in a large skillet over medium heat, then cook the mushrooms and half the onion for about 5 minutes, until the mushrooms soften and the onion turns translucent.
4. Make the sauce. Whisk the milk, cornstarch, soy sauce, salt, and pepper in a measuring cup, pour it over the mushrooms, and stir regularly over low medium heat for 5 to 10 minutes, until thick enough to coat a spoon.
5. Bake. Pour the sauce over the beans, stir gently to coat, and bake for 20 minutes, until bubbling.
6. Fry the onions. While the casserole bakes, toss the remaining onion strips in the flour, then fry in 350 degrees F oil in small batches for 2 to 3 minutes, until golden. Drain on paper towels.
7. Top and rest. Scatter the hot onions over the casserole and let it stand for 5 minutes before serving.
How to Serve Southern Green Bean Casserole
Serve this casserole hot as part of a classic Sunday spread. It is a natural side for dutch oven pot roast or Yukon gold crock pot roast. For a bigger seasonal table, add homemade buttery herb stuffing and a basket of fluffy homemade dinner rolls to mop up the sauce.
How to Store and Reheat Southern Green Bean Casserole
Cool within two hours, then refrigerate covered for 3 to 4 days, keeping the crispy onions in a separate container so they do not go soft. Reheat covered at 350 degrees F for about 20 minutes, until it reaches 165 degrees F, and top with the onions afterward. The milk sauce does not freeze well, so plan to eat it within a few days.
Tips and Variations for Southern Green Bean Casserole
Use frozen beans. Thaw 8 cups and drain well, then boil only 8 to 10 minutes, since frozen beans soften faster.
Mix your mushrooms. Cremini or shiitake add deeper flavor than white mushrooms.
Prep the sauce early. Make the sauce up to a day ahead, refrigerate, and assemble just before baking.
Fry safely. Keep a thermometer in the oil, never leave the pan unattended, and add the onions in small batches so the oil stays hot.
Take a shortcut. Short on time? Use store bought crispy onions and add them in the last 5 minutes of baking.
Boost the umami. A teaspoon of Worcestershire sauce stirred into the sauce adds extra depth.
Check the thickness. The sauce should coat a spoon before baking, since it loosens slightly as it heats with the beans.
Store safely. Chill the dish quickly after the meal. The University of Wisconsin Extension leftover food safety article offers general advice on cooling and storing leftovers.
Frequently Asked Questions About Southern Green Bean Casserole
How long do you boil beans for southern green bean casserole?
Boil them about 15 minutes, until fork tender. They finish softening in the sauce, so do not cook them past tender.
Can I make southern green bean casserole without canned soup?
Yes, and that is the point. The mushroom, milk, and cornstarch sauce replaces canned soup and tastes fresher and lighter.
Can I prepare southern green bean casserole in advance?
Yes. Make the sauce a day early and keep the beans and sauce separate. Combine, bake, and fry the onions just before serving.
What can I use instead of soy sauce?
Coconut aminos work in the same amount. A teaspoon of Worcestershire sauce with an extra pinch of salt is another option.
How do I keep the fried onions crisp?
Drain them on paper towels and add them to the casserole only when it comes out of the oven.
Homemade Southern Green Bean Casserole
Equipment
- Large skillet
- Whisk
Ingredients
Main Ingredients
- 8 cup fresh green beans trimmed and cut into 1 inch pieces
- 2 tbsp unsalted butter
- 8 oz white mushrooms sliced
- 1 small yellow or Vidalia onion cut into thin strips, divided
- 2 cup whole milk
- 2 tbsp cornstarch
- 2 tbsp low sodium soy sauce
- ¼ tsp salt
- ¼ tsp black pepper
- 1 cup all purpose flour for coating the onions
- 1 ½ cup neutral oil for frying; most stays in the pan
Instructions
Cooking
- Preheat. Set the oven to 350 degrees F and grease a 13×9 inch dish. Soften the beans. Simmer the beans in water about 15 minutes until fork tender, then drain and spread in the dish.
- Saute. Melt the butter and cook the mushrooms and half the onion about 5 minutes until soft.
- Thicken. Pour in the whisked milk mixture and stir 5 to 10 minutes over low medium heat until it coats a spoon.
- Bake. Stir the sauce into the beans and bake 20 minutes until bubbling.
- Fry. Coat the remaining onion in flour and fry in 350 degrees F oil 2 to 3 minutes per batch until golden.
- Serve. Top with the onions and rest 5 minutes.
