Instant Pot green bean casserole turns a Thanksgiving classic into a one pot side dish that cooks in minutes under pressure.
Tender green beans and sauteed mushrooms are folded into a creamy sauce and crowned with golden crispy onions. You skip the long oven bake, which frees up valuable oven space on a busy dinner table.
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Why This Instant Pot Green Bean Casserole Recipe Works
Pressure cooking steams the green beans until just tender in only four minutes, so they keep a pleasant bite instead of turning soft and gray. The mushrooms and onions cook in the same pot, which means more flavor and fewer dishes.
A quick flour and Parmesan mixture thickens the sauce right in the pot, and the condensed mushroom soup adds familiar creamy flavor. The oven toasted onions on top bring back the crunch that makes the dish a favorite.
Ingredients for Instant Pot Green Bean Casserole
- 3 tablespoons unsalted butter, divided
- 1/2 cup diced onion
- 8 ounces sliced mushrooms
- 2 cloves garlic, minced
- 1 1/2 pounds green beans, trimmed and cut into 2 inch pieces
- 1 cup vegetable broth
- 1 cup crispy fried onions, for topping
- 2 tablespoons all purpose flour
- 2 tablespoons freshly grated Parmesan cheese
- 1 can (10.75 ounces) condensed cream of mushroom soup
- 1 pinch kosher salt
- 1/4 teaspoon black pepper
Green beans. Fresh green beans cook evenly and stay bright green under pressure. Trim the ends and cut them into uniform pieces.
Mushrooms and onion. They build the savory base. Cook the mushrooms until they release their liquid and begin to brown.
Cream of mushroom soup. Stirred in at the end, it gives the sauce its familiar creamy body without any extra simmering.
Flour and Parmesan. Mixed with melted butter, they thicken the sauce and add a gentle salty richness.
Crispy fried onions. Toast them in the oven for a few minutes so they stay crunchy when sprinkled over the casserole.
How to Make Instant Pot Green Bean Casserole
1. Heat the oven Preheat the oven to 400 degrees F and line a baking sheet with parchment paper.
2. Saute the onion Press the Saute button on the pot, melt 1 tablespoon of butter, and cook the onion for 3 to 4 minutes until translucent.
3. Cook the mushrooms Add the mushrooms and cook for 5 to 6 minutes until softened. Stir in the garlic for 30 seconds and season with salt and pepper.
4. Pressure cook the beans Add the broth and green beans, press Cancel, seal the lid, and cook on high pressure for 4 minutes, then use a quick release.
5. Toast the onions While the beans cook, spread the fried onions on the baking sheet and bake for 5 to 7 minutes until golden.
6. Make the thickener Melt the remaining 2 tablespoons of butter and stir it with the flour and Parmesan in a small bowl.
7. Finish the sauce Open the lid, press Saute, stir in the flour mixture and the soup, and cook until thickened. Top with the crispy onions.
How to Serve Instant Pot Green Bean Casserole
Spoon the casserole into a serving dish and top it with the crispy onions right before bringing it to the table. It belongs next to creamy mashed potatoes and gravy and a basket of soft dinner rolls on any roast dinner. It also works alongside tender pot roast and oven baked barbecue chicken for a simple weeknight meal. Serve it hot, and keep extra onions on the side so guests can add more crunch.
How to Store and Reheat Instant Pot Green Bean Casserole
Cool the casserole and store it in an airtight container in the refrigerator for up to 3 days. Keep any extra crispy onions in a separate container at room temperature so they stay crunchy. To freeze, skip the onion topping and freeze the beans in sauce for up to 2 months, then thaw overnight in the refrigerator. Reheat in a saucepan or microwave until steaming hot, 165 degrees F, and add a splash of broth if the sauce looks thick. Top with fresh onions after reheating.
Tips and Variations for Instant Pot Green Bean Casserole
Trim evenly. Cut the beans into pieces of equal length so they all finish at the same time.
Do not overcook. Four minutes under high pressure keeps the beans tender with a slight bite. Longer times make them soft.
Release carefully. Use the quick release method and keep your hands away from the steam vent.
Use fresh mushrooms. Cremini or white mushrooms both work well. Slice them evenly so they cook at the same pace.
Adjust the thickness. Stir in a splash of broth if the sauce becomes too thick after standing.
Make a lighter sauce. Replace half the condensed soup with plain Greek yogurt for a tangier, lighter sauce.
Finish in the oven. For a bubbly top, transfer the casserole to a baking dish, add the onions, and broil for 2 minutes.
Serve it safely. Keep the dish hot until serving. For general guidance on storing leftovers, see the Purdue Extension guide to storing leftovers.
Frequently Asked Questions About Instant Pot Green Bean Casserole
Can I make Instant Pot green bean casserole ahead of time?
Yes. Cook the beans and sauce a day ahead and refrigerate. Reheat gently and add the fried onions just before serving.
How long does Instant Pot green bean casserole keep?
Refrigerate it in an airtight container for up to 3 days. Keep the crispy onions separate so they stay crunchy.
Can I freeze Instant Pot green bean casserole?
Yes, freeze it without the onion topping for up to 2 months. Thaw overnight in the refrigerator and top with fresh onions.
Do I need to bake it after pressure cooking?
No. The casserole is ready as soon as the sauce thickens. The oven is only used to toast the onions.
Can I use fresh onions instead of fried onions?
You can, but the topping will not be crunchy. Try toasted panko or crushed crackers for a similar texture.
Instant Pot Green Bean Casserole with Crispy Onions
Equipment
- Instant Pot
- Baking sheet
- Parchment paper
Ingredients
Main Ingredients
- 3 tbsp unsalted butter divided
- ½ cup onion diced
- 8 oz sliced mushrooms
- 2 cloves garlic minced
- 1 ½ lb green beans trimmed and cut into 2 inch pieces
- 1 cup vegetable broth
- 1 cup crispy fried onions for topping
- 2 tbsp all purpose flour
- 2 tbsp Parmesan cheese freshly grated
- 10.75 oz condensed cream of mushroom soup 1 can
- 1 pinch kosher salt
- ¼ tsp black pepper
Instructions
Cooking
- Toast the onions. Heat the oven to 400 degrees F and bake the fried onions on a lined sheet for 5 to 7 minutes until golden.
- Saute. On the Saute setting, melt 1 tablespoon of butter and cook the onion 3 to 4 minutes, then the mushrooms 5 to 6 minutes. Add the garlic for 30 seconds.
- Pressure cook. Add the broth and green beans, seal the lid, and cook on high pressure for 4 minutes with a quick release.
- Thicken. Stir the flour, Parmesan, and 2 tablespoons melted butter together, then stir them into the pot with the soup on Saute until thick.
- Top and serve. Sprinkle with the toasted onions and serve hot.
