Green Bean Casserole Recipe

A comforting green bean casserole with crispy fries, mushrooms, and a creamy sauce, baked to perfection for a hearty side dish.

One playdate, I watched my son go back for thirds of green beans. He had always hated them, and we were both surprised by how much he enjoyed them this time. I knew I had to try making my own version at home. But what's this health-obsessed mom to do to get her kid to eat green beans? Combine them with fries, of course.

Now, alongside the infamous air fryer zucchini fritters, the combination of crispy shoestring fries, tender green beans, and savory mushroom sauce has become our go-to answer for "What should we bring?"—whether it's a summer potluck party or a winter holiday gathering.

I never imagined my picky eater asking for green beans or air fryer asparagus for dinner, yet here we are.. He'd instantly assume we're having this when he smells the sweet aroma of caramelized onions - the same way I prepare them for my lentil and rice with caramelized onion recipe..

It also pairs well with plenty of options. Sometimes I serve it with air fryer BBQ chicken drumsticks or juicy air fryer turkey thighs. If we want something else, I go with lemon air fryer salmon or air fryer tofu.

This single dish changed our family's relationship with vegetables. My son loves green beans even more now, and my daughter finishes her plate—as long as the shoestring fries outnumber the vegetables. Some days, they compete to see who can finish more servings.

From the beginning, I made sure this recipe could adapt to different seasons and occasions. During summer BBQs, it holds up well on buffet tables with grilled meats. In the winter holidays, it adds a fresh, vibrant touch to heavier dishes. I love that something as simple as green beans can be enjoyed and appreciated by everyone at the table—even those who are usually skeptical of veggies.

Ingredients

• Fresh Green Beans – The star of the dish, bringing a fresh crunch. I’ve tried using canned green beans, but fresh ones deliver better texture and flavor. The key is trimming and cutting them into 1-inch pieces for even cooking.
• Mushrooms – These add earthy umami flavor that enhances the dish. I prefer cremini mushrooms for their deeper taste. I’ve used white button mushrooms, but the cremini have a richer flavor.
• Onion – Adds natural sweetness to the mix. I caramelize them for about 10 minutes to bring out the richness.
• Garlic – Brings a fragrant, savory note to the dish. I’ve experimented with garlic powder, but freshly minced garlic has a stronger, more aromatic flavor that spreads evenly throughout.
• Olive Oil or Butter – These are the fats used for sautéing the vegetables. I often choose olive oil for a lighter touch, but butter creates a richer flavor. 
• All-Purpose Flour – Essential to help thicken the sauce and bind the ingredients together.
• Vegetable or Chicken Broth – Serves as the base for the sauce. I often use vegetable broth for a lighter flavor, but chicken broth adds more depth. I prefer chicken broth for a richer, heartier sauce, but both options work well.
• Milk (or Non-Dairy Milk) – Adds creaminess to the sauce. I typically use whole milk for a richer, smoother texture, but almond milk works when I need a dairy-free option. 
• Frozen Shoestring Fries – Create a crispy topping for the casserole. These fries crisp up quickly and give the dish a golden, crunchy finish without the extra effort. Shoestring fries are the perfect size and texture, adding crunch with minimal hassle.

See the recipe card for exact quantities.

Step-by-step Instructions

This green bean casserole is a comforting dish with a creamy mushroom sauce and crispy shoestring fries on top. It’s a perfect side dish for any meal, combining savory flavors with a satisfying crunch. Easy to prepare and made with simple ingredients, it’s a guaranteed hit at the dinner table. 

Prepare the Fries

Arrange the shoestring fries in a single layer on a baking sheet. Bake them in the preheated oven for about 15 minutes or until they are golden and crispy. Set aside once they’re done.

Sauté the Vegetables

In a large skillet, heat either olive oil or butter over medium heat. Add the sliced onion and cook it until caramelized, which will take about 10 minutes. Stir occasionally to make sure the onions cook evenly and don't burn.

Add Mushrooms and Garlic

Next, add the sliced mushrooms and minced garlic to the skillet with the caramelized onions. Cook them together for 5-7 minutes, or until the mushrooms have softened and released their moisture. Once the liquid has evaporated, the mushrooms will be tender and ready for the next step.

Add Soy Sauce and Flour

Pour the soy sauce over the mushrooms and onions, stirring to combine. The soy sauce adds depth of flavor to the dish. Then, sprinkle the flour over the mushroom mixture and stir it in well. Let it cook for 1-2 minutes to remove the raw flour taste.

Add Broth and Milk

Gradually pour in the vegetable or chicken broth while stirring constantly. This helps the mixture thicken. Once the sauce thickens, add the milk, and stir to combine. Taste the sauce and adjust the seasoning with salt and pepper. Stir everything until smooth.

Add Green Beans

Add the green beans to the skillet with the mushroom sauce. Mix everything together so the green beans are fully coated in the sauce.

Assemble the Casserole

Grease a 9x13-inch baking dish and pour the green bean and mushroom mixture into the dish. Spread it out evenly and place it in the oven preheated to 350°F (175°C). Bake for 20 minutes to heat through.

Top with Fries

Remove the casserole from the oven and top it with the crispy shoestring fries. Return the dish to the oven and bake for an additional 10-15 minutes, or until the fries are golden and crispy and the casserole is fully heated through.

Serve and Enjoy!

Serve this green bean casserole hot, straight from the oven, with the fries golden and crisp on top.

Storage

To store the green bean casserole, let it cool to room temperature before transferring it to an airtight container. Refrigerate for up to 3-4 days. If you want to freeze it, portion the casserole into freezer-safe containers and remove as much air as possible to prevent freezer burn. To reheat, thaw the casserole overnight in the refrigerator, then bake it at 350°F (175°C) for about 20-25 minutes, until heated through. You can also microwave individual servings in 1-minute intervals, stirring between each, until warm.

Recipe