Panko Parmesan Topped Green Bean Casserole Recipe

Name: Panko Parmesan Topped Green Bean Casserole Recipe
Prep time: 45 min
Cook time: 45 min
Total time: 1 h 30 min
Yield: 8
Cuisine: Continental
Ingredients: 6 tbsp unsalted butter, divided; 2 tbsp olive oil, divided; 1 large sweet onion, sliced; 1 (8 oz) pkg sliced cremini mushrooms; 3 cloves garlic; 3 tbsp flour; 3 cups whole milk; 2 tsp Worcestershire sauce; 6-7 shakes tabasco sauce; ½ tsp salt; ½ tsp pepper; 1 tbsp fresh thyme, minced; ¼ cup grated parmesan cheese; 2 lbs fresh French style green beans, rinsed and stems removed; ½ cup Kikkomon Panko Bread Crumbs; ⅓ cup grated parmesan cheese; 2 tbsp fresh parsley, minced

Holiday | Side Dishes | Thanksgiving | Vegetable

ByLisa November 3, 2023February 17, 2025

131 Comments

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Fresh green beans, caramelized onion, mushrooms and a homemade béchamel sauce combine with a crunchy Kikkoman Panko Bread Crumb topping to create this scrumptious Panko Parmesan Topped Green Bean Casserole. A fresh take on a holiday classic.

Traditional Green Bean Casserole Origins

Dorcas Reilly. Although unrecognized to many of us, almost every homemade green bean casserole made in the last 60+ years can be traced back to one Dorcas Reilly.

She was an employee of the Campbell Soup Company and worked in their Test Kitchen creating new recipes using Campbell Soup. In 1955, she was credited with creating what we now know as the traditional green bean casserole. Well done, Dorcas Reilly!

Classic Thanksgiving Side Dish

It is very likely you have had a holiday meal that featured a classic green bean casserole made from canned green beans, canned cream of mushroom soup, milk and crispy fried onions. As a child, our Thanksgiving table definitely had this traditional green bean casserole as part of our holiday meal.

As an adult, I’ve been hosting our family’s Thanksgiving dinner for many years and I continue to enjoy having everyone over. While much of the menu remains the same year after year, I do like to tweak a favorite recipe or come up with a new recipe altogether.

Updating the Classic Green Bean Casserole Recipe

For years, I made a relatively simple green bean dish that we all love (Fresh Green Beans with Shallot Butter Sauce) for our Thanksgiving dinner, but I thought it was time to break out of my box and try something new. Homemade green bean casserole is certainly not a new thing, but I felt it was a recipe that could be improved with some updating.

The first step to update this casserole was to freshen up the ingredients with fresh green beans, caramelized onion, fresh mushrooms and homemade béchamel. The fresh green beans add a great snap that no canned green beans have and the creamy mushroom sauce is delicious and much lower in sodium than a can of cream of mushroom soup.

But what about the crispy onion topping?

Now, I’m a big fan of crispy fried onions. Pair them with steak tips, put them on a burger or just eat them right from the can! Definitely delicious.

But as I said, I like to experiment with and tweak traditional recipes. Every homemade green bean casserole needs a crunchy topping, so I combined Kikkoman Panko Bread Crumbs, parmesan cheese, parsley and melted butter to get that delicious crunch. And, you still get the onion flavor from the caramelized onions.

I love using Kikkoman Panko Bread Crumbs because they’re made with custom baked bread that makes airy, crispy crumbs, and they’re toasted to a delicate crunch that won’t burn as easily. That means my topping ended up extra crispy and delicious.

The bread crumbs come packed in a resealable bag that helps them to stay fresh longer, which I love because that means no waste.

Make Ahead

This is also a great make ahead recipe. See Tips and Tricks below on what can be cooked ahead of time and how to store.

Basically, most of this fresh green bean casserole recipe can be prepared a day or two in advance. If you do this, on the day you’re ready to serve this Panko Parmesan Topped Green Bean Casserole, all you need to do is prepare the panko bread crumb topping.

Once the casserole is assembled, it’s ready to bake according to the instructions. 45 minutes later, you have the perfect side dish to serve with your Thanksgiving dinner!

Enjoy!

Tips and Tricks

This casserole does involve a few steps, but the great thing is, you can do most of the preparation ahead of time.
The onions and mushrooms can be cooked up to a couple of days ahead of time and stored in the fridge.
It’s also fine to make the béchamel sauce up to a day ahead of time and store in the fridge. If the sauce seems a little too thick when you’re ready to assemble the casserole, just thin it out with a little bit of milk.
Store all of the ingredients separately in the refrigerator (except for the panko bread crumbs). Assemble the casserole right before you’re ready to bake it.
Wait until the day you’re going to assemble and bake the green bean casserole to prepare the panko bread crumb topping.
Reheat any leftover green beans by putting them in a cold oven (in an oven safe dish). Then turn the oven to 350 degrees. As the oven warms up it gently reheats the casserole. Once the oven has finished preheating, the casserole should be up to temperature at that point or shortly thereafter.

Ingredients Needed to Make This Green Bean Casserole

Full instructions can be found below in the printable recipe card

Butter – Unsalted butter is recommended to prevent the dish from becoming too salty.
Olive oil
Sweet onion – I like to use Vidalia, but Walla Walla or Maui onions are also good choices.
Cremini mushrooms – I prefer these over white button mushrooms. I feel they have more depth of flavor.
Garlic
Flour
Whole milk – This is highly recommended. Whole milk will make a much richer béchamel than skim, 1% or 2% milk.
Worcestershire sauce
Tabasco sauce
Salt
Pepper
Fresh thyme – Highly recommend fresh thyme over dried as it imparts a fresher flavor.
Grated parmesan cheese – You can use the green can cheese, but I highly recommend the grated parmesan cheese you find in the refrigerated section of the grocery store. It tastes so much better!
Fresh French style green beans – These are thin green beans. If you can’t find fresh French style green beans, you can use regular green beans, as long as they’re fresh.
Panko bread crumbs – I highly recommend the Kikkoman brand panko bread crumbs.
Fresh Italian parsley – This adds a nice brightness to the finished casserole.

How to Make Panko Parmesan Topped Green Bean Casserole

Preheat oven to 350 degrees.
Heat 1 tbsp unsalted butter and 1 tbsp olive oil in a large skillet over medium-low heat.
Add sliced onion and cook, stirring often, until onion is golden brown and caramelized, about 30 minutes.
Remove onion from skillet and set aside.
Heat remaining 1 tbsp olive oil in the same skillet over medium heat.
Add mushrooms and sauté until browned, about 10 minutes.
Remove from skillet and set aside with onion.
Heat 3 tbsp butter in a 2 quart saucepan over medium heat.
Add garlic and cook for 1 minute, until garlic is fragrant.
Whisk in flour and let cook for another minute.
Gradually whisk in milk, being careful not to let lumps form.
Bring mixture to a bubble and cook until sauce has thickened, continuing to whisk.
Whisk in Worcestershire sauce, tabasco, salt, pepper, thyme and ¼ cup parmesan.
In a large bowl, combine onion, mushrooms, fresh green beans.
Pour sauce over mixture and stir until well coated.
Transfer mixture to a 9×13 baking dish or a large skillet (cast iron) that’s been coated with cooking spray.
Melt remaining 2 tbsp of unsalted butter.
Combine with panko, ⅓ cup parmesan and parsley, until mixture is well coated with the butter.
Top green bean mixture with panko mixture.

More Holiday Recipes to Enjoy

Yield: 8-10