Healthy Green Bean Casserole

The best healthy Green Bean Casserole that is perfect for any holiday meal and tastes absolutely amazing. This upgraded version with fresh green beans and almonds is better than the original.

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This year I am all about taking classic holiday dishes and giving them a lighter, modern twist. Today’s task - the ultimate canned soup classic - Green Bean Casserole. However, we are ditching the canned mushroom soup, canned green beans, and canned crispy onions to make an incredibly tasty, fresh version of this beloved dish. Casserole lovers, you'll also want to check out this Healthy Broccoli Casserole.

Trust me, it is so much better than the canned version and just as easy to make. Truth be told, I was never a fan of green bean casserole until I started making it from scratch with fresh green beans and homemade gravy. Other than the crunchy onions on top, which are surprisingly delicious, I didn't understand the appeal. Mushy green beans are not for me. 

This version is anything but mushy. The green beans are bright green and still have some crunch. The crispy almond, onion, and breadcrumb topping is addictively delicious. It's hard to stop eating it and you will probably want to put it on everything. Then there is the rich, mushroom gravy. This dish will be a hit on any holiday table. 

Green bean casserole with fresh green beans, mushroom gravy, and a crispy onion topping in a baking dish with a wooden spoon.

The Secret to Delicious and Healthy Green Bean Casserole

There are two secrets to making a lightened up Green Bean Casserole. The first is nailing that crispy onion topping without reaching for a can or deep fryer. The second, and most important, is creating a super flavorful mushroom gravy without depending on tons of heavy cream, butter, or canned soup. This is where my secret ingredient comes in.

One of my all-time favorite ways to build rich, deep flavor without a million ingredients or tons of fat is to use bouillon cubes or paste. I like to think of these as little flavor bombs that add rich, deep, umami flavor without needing to spend hours making homemade stock or adding tons of spices and herbs. All the flavor you need is packed into these convenient little cubes.

The other reason I like using bouillon is that gives you that rich, deep flavor without needing to add tons of fat or extra ingredients. Now when it comes to bouillon, not all options are created equal. Usually, I look for an option that is free from MSG and lower in sodium. Typically I am reaching for Better than Bouillion or BOU cubes (vegetarian). You can also use homemade. 

Now that you know the secret, let’s talk about what makes this recipe so good.

How to Make Green Bean Casserole

First – it starts with fresh green beans that are cooked until tender crisp. No mushy green beans in this casserole.

Next comes the mushroom gravy. It starts with cremini mushrooms sautéed in a touch of butter and lots of garlic. Once they get nice and tender, it’s time to make the gravy using low-fat milk, whole wheat flour, and chicken or vegetable bouillon.

The bouillon adds that rich, savory flavor that makes the gravy taste indulgent without using all the butter and heavy cream traditionally used in green bean casserole. This is tossed with the green beans.

To finish things off, you can’t have green bean casserole without the crispy onion topping. For mine, I always start with shallots, since they have plenty of onion flavor without the bite. Those are cooked down and then tossed with toasted Panko breadcrumbs and sliced almonds. The almonds add nuttiness and are always a good idea with green beans.

Everything takes a trip to the oven and within about 15 minutes, you have the most amazing, lightened up, flavor packed Green Bean Casserole. It should be on every holiday table in my opinion.

Can I make this in advance?

Since you want the green beans to be fresh with some crunch, I don’t recommend making this ahead of time. However, you can blanch the green beans and make the mushroom gravy 1-2 days in advance. Store the green beans and sauce separately in the fridge. Then just assemble and bake.

Recipe Ideas and Tips

  • Kick up the holiday flavor with some fresh nutmeg in the mushroom gravy.
  • For more onion flavor, use red onion or sweet Vidalia onion in place of the shallots.
  • Add fresh herbs like thyme or rosemary.
  • For a gluten-free option, use gluten-free breadcrumbs.
  • For a vegan option, use plant-based milk.
  • If you love cheese, consider adding some Parmesan cheese to the breadcrumb topping and mushroom gravy.

Storage and Reheating

  • Storing: If you are storing this dish after it is cooked, make sure to keep it in an airtight container. It will last 3-4 days in the fridge. 
  • Reheating: Reheat the green bean casserole in the oven at 350 degrees until it is bubbling slightly and warmed through. Cooking time will depend on how much you are reheating. It can also be reheated in the microwave, but it may lose some crunch. 

Lighter green bean casserole with cripsy onions, fresh green beans, and mushroom sauce in a white baking dish.

How to choose green beans?

This recipe gets a lot of flavor from the fresh, crisp green beans, When choosing green beans in the store, make sure to look for green beans that are bright in color without brown spots or bruising. They should be firm without wrinkling. Also if you snap one in half, it should be a crispy break. Avoid soggy or limp green beans.

To prepare them for cooking, start by washing them well to remove any dirt and debris. Then trim off the ends and cut any extra long beans in half for easier eating. For a shortcut, look for green beans that have already been trimmed. 

More holiday side dish recipes

The Recipe
Healthy Green Bean Casserole with green beans, mushroom sauce, and a crispy almond onion topping in a baking dish with a striped napkin.

Healthy Green Bean Casserole

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  • 2 lbs. green beans
  • 2 tbsp butter, divided
  • 1 cup shallots, thinly sliced
  • 1/2 cup panko breadcrumbs
  • 1/4 cup sliced almonds
  • 10 oz. cremini mushrooms, sliced
  • 3 garlic cloves, minced
  • 2 tbsp white whole wheat flour
  • 2 cups reduced fat milk
  • 2 vegetable bouillon cubes (or chicken)
  • Salt and pepper to taste

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Preheat the oven to 400 degrees Fahrenheit.


Bring a large pot of water to a boil. Add the green beans and cook 3-4 minutes until bright green and tender crisp. Immediately add to an ice bath to stop the cooking. Strain and dry.


Melt 1 tbsp. of butter in a pan over medium heat. Add the shallots and cook 5-7 minutes until tender but still maintaining their shape. Remove. Add the breadcrumbs to the pan and toast for 1-2 minutes until light brown. Add to the cooked shallots. Stir in the sliced almonds. Set aside.


Wipe out the pan with a paper towel. Add the remaining 1 tbsp. of butter. Once melted, add the mushroom and cook 6-8 minutes until tender. Add the garlic and cook 1 minute. Add the flour and stir well. Cook for 1 minute. Add the milk and bouillon cubes. Bring to a simmer and cook for 6-8 minutes, stirring often, until thick and creamy. Taste and season with salt and pepper as needed.


Spray a large baking dish with cooking spray. Add the green beans and mushroom gravy, Stir to combine. Add the crispy onions on top.


Bake for 20-25 minutes until browned and bubbly. Serve.

Nutritional Facts
Serving Size: 1 cup
Amount Per Serving
Calories 155
Calories from Fat 55
% Daily Value *
Total Fat 6g
Saturated Fat 3g
Monounsaturated Fat 0g
Polyunsaturated Fat 0g
Cholesterol 13mg
Sodium 55mg
Total Carbohydrate 21g
Dietary Fiber 4g
Sugars 9g
Protein 7g

* Percent Daily Values are based on a 2,000 calorie diet. Your daily values may be higher or lower depending on your calorie needs.

The Nutritional Values provided are estimates only and may vary based on the preparation method.

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About the author Meet Kristen McCaffrey
Hi, I’m the cookbook author, recipe developer, and food enthusiast behind Slender Kitchen. I am obsessed with making healthy food that is easy to prepare and absolutely delicious. Meal planning is my secret weapon and I hope I can make meal time easier for you with our tried and tested recipes and foolproof meal plans. Learn More
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