How To Reheat Green Bean Casserole – I Test 5 Methods [Pics]

Thanksgiving leftovers can never go to waste – it’s a sin! But some dishes, like green bean casserole, never seem as appetizing the next day (unless you know how to reheat them properly).

I experimented with five different reheating methods to see which one worked best and got my casserole tasting as good as new. Here’s what I found.

The best way to reheat green bean casserole is in the oven. Preheat your oven to 350°F (180°C). Allow the casserole to reach room temperature and add a few tablespoons of stock. Reheat the green bean casserole in the oven for 15-30 minutes. Once it’s hot, remove the foil and add new crispy onions.

I tested how to reheat green bean casserole

I whipped up a green bean casserole for dinner and put aside a few portions for my reheating experiment.

The following day, I reheated the leftover casseroles using the following methods:

• In the oven (or air fryer): The best way.
• In the microwave: Okay if you’re in a rush.
• On the stove: Pretty good.
• In a slow cooker: Not safe.

Reheating green bean casserole in the oven

Time: 15-30 minutes
Rating: 9/10

1. Take the casserole out of the fridge and let it reach room temperature.
2. Preheat your oven to 350°F (180°C).
3. Add a few tablespoons of stock to the casserole dish and cover it with foil.
4. Heat it in the oven for 15-30 minutes (depending on portion size).
5. When it’s hot and bubbly, remove the foil and add some crispy new onions.
6. Put the casserole back in the oven for a further 5 minutes to crisp the top.

If you don’t have any crispy onions, then breadcrumbs, crunched nuts, or crushed chips will work just as well. Or you can top the casserole with some extra grated cheese.

It is best to let the casserole reach room temperature before reheating it. That way, the casserole will heat more evenly and faster than if it went in the oven straight out of the fridge.

Psst…. you can also use your air fryer in a similar way to the oven, but reduce the heating time because air fryers are smaller.

Results: This was the best method I tried. The casserole warmed evenly and wasn’t too soft. I also loved how easily I got a nice crispy top. And it’s a versatile method that’s good for big and small portions.

Reheating green bean casserole in the microwave

Time: 30 seconds
Rating: 7/10

1. Spoon a portion of green bean casserole into a microwave-safe bowl.
2. Sprinkle a little water over the casserole and cover the bowl with plastic wrap.
3. Heat in the microwave at 30-second intervals until it’s hot, stirring a bit during each break.

Vegetables overcook quickly in the microwave, and you don’t want mushy beans! That’s why I suggest 30 seconds at a time. Then you can take the casserole out as soon as it’s hot. 

It’s best to let the casserole rest for 30 seconds before digging in. This allows the heat time to equalize throughout the dish and means you won’t burn your mouth.

Results: I wasn’t very impressed with the results from the microwave. The beans were a bit limp, and the sauce was a bit thin. If you’re just heating a portion for yourself and you’re in a rush, the microwave is fine, but if you’re serving other people, I’d avoid it.

Reheating green bean casserole on the stove

Time: 5-10 minutes
Rating: 9/10

1. Heat a pan over low-medium heat.
2. Spoon your leftover green bean casserole into the pan.
3. Add 1-2 tablespoons of water or stock if needed to loosen the sauce.
4. Place a lid on the pan to keep the steam in.
5. Stir the casserole frequently until it’s piping hot.
6. Serve and top with crispy onions if you have any.

Heating the casserole over a lowish heat is slower, but it won’t dry the beans out or leave you with parched sauce. You’ll find that the sauce thickens in the fridge, so a little water or stock will help smooth the sauce out.

Pro tip: To crisp the top transfer the casserole to an oven-safe dish and put it under the broiler for 1-2 minutes before serving.

Results: This method worked pretty well as an alternative to the oven (and it was faster). The only downside is not being able to get as crispy a top. Adding some crispy onion does help, but it’s just not the same.

Reheating green bean casserole in a slow cooker

Some sources online suggest you can reheat leftover green bean casserole in a slow cooker, but this isn’t advisable for safety reasons. Because a slow cooker can take so long to heat things up, your casserole may end up spending too much time in the ‘danger zone’ for bacteria, which is between 40°F and 140°F.

Instead, you should reheat your green bean casserole using another method like the oven or the stovetop, and then use the slow cooker to keep it warm.

How to store green bean casserole

Once you’ve cooked the green bean casserole, let it cool to room temperature. Then transfer it to an airtight container and pop it in the refrigerator. The crispy onions will go soft, so add new ones when you reheat the dish. Green bean casserole lasts 4-5 days when refrigerated.

Don’t leave the green bean casserole out at room temperature for more than two hours. After this, bacteria can start multiplying in your casserole.

If you need to cool a big batch, separate it into smaller shallow containers so the heat can escape more easily. I really recommend cooling the dish before storing it because otherwise, condensation will build up in the container and drip down into the dish, leaving you with a watery sauce.

Can you freeze green bean casserole?

It’s safe to freeze green bean casserole, but I would avoid it if you can. The green beans go soft, and the soup can separate slightly when frozen. If you do want to freeze the casserole, leave off the crunchy topping and coat the green beans in cornstarch to help stabilize the sauce.

Green bean casserole lasts up to 3 months in the freezer. It will remain safe to eat beyond this, but the quality will suffer.

How to freeze green bean casserole:

1. Let the casserole cool to room temperature.
2. Keep it in an oven- and freezer-safe dish (aluminum trays are a good option). For smaller portions, put the casserole in a freezer bag.
3. Cover the dish with a layer of plastic wrap followed by a layer of foil. Or remove all the excess air from the freezer bag.
4. Label and date the casserole before placing it in the freezer.
5. Eat the green bean casserole within 3 months. 

Disposable aluminum trays are convenient as they allow you to freeze and then heat the dish directly from the freezer.

I use a double layer of protection because this will help prevent freezer burn.

How to reheat frozen green bean casserole

You can thaw the frozen casserole in the fridge overnight and then heat it in the oven. Or you can heat the casserole directly from frozen in the oven, but you’ll need to allow extra time to ensure it heats through.

Preheat the oven to 350°F (180°C). Remove the plastic wrap and the foil from the frozen casserole dish. Cover the dish with new foil, and then bake for between 40 and 45 minutes. Once the casserole is warmed through, add some crispy onions and then bake for a further 5 minutes.

How To Reheat Green Bean Casserole

In this short recipe, I show you the best way to revive and reheat your leftover green bean casserole.

5 from 1 vote

Print Pin Rate

Course: Side Dish

Cuisine: American

Keyword: green bean casserole, reheat green bean casserole

Prep Time: 0 minutes minutes

Cook Time: 15 minutes minutes

Total Time: 15 minutes minutes

Servings: 1 portion

Calories: 161kcal

Ingredients

• 1 portion green bean casserole
• 1 portion crispy onions optional
• 2 tbsp stock or water

Instructions

• Take the casserole out of the fridge and let it reach room temperature.
• Preheat your oven to 350°F (180°C).
• Add a few tablespoons of stock or water to the casserole dish and cover it with foil.
• Reheat it in the oven for 15-30 minutes (depending on portion size).
• When it’s hot and bubbly, remove the foil and add some crispy new onions.

  Put the casserole back in the oven for a further 5 minutes to crisp the top.

Notes

If you don’t have any crispy onions, then breadcrumbs, crunched nuts, or crushed chips will work just as well.

Anything that can add a bit of a crunch.

You can even top the casserole with some extra grated cheese.

It is best to let the casserole reach room temperature before reheating it.

That way, the casserole will heat more evenly and faster than if it went in the oven straight out of the fridge.

Nutrition

Serving: 100g | Calories: 161kcal