Smoked Green Bean Casserole

Ramp up the flavors of your green bean casserole with homemade fried onions and smoke!
smoked green bean casserole

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Arguably one of the most popular Thanksgiving side dishes, the humble Green Bean Casserole is a fantastic addition to any Thanksgiving table.

With just a few simple ingredients, it’s packed full of flavor and pairs perfectly with Thanksgiving mains like turkey and ham.

Level up your green bean casserole by cooking it on the smoker. This will add a nice, even layer of smoky flavor to the dish, really bringing it to the next level.

How to make Smoked Green Bean Casserole

Let’s be honest: most of us have memorized the recipe for green bean casserole. The recipe is popular and can even be found on a can of green beans or cream of mushroom soup around this time of year.

I like to make my fried onions from scratch. Homemade fried onions add an extra layer of texture and flavor to the dish and will keep your guests coming back for seconds (and thirds!).

The famous casserole combines canned green beans, cream of mushroom soup, milk, soy sauce, seasoning, and a fried onion topping. If you want to get fancy, I also have a version of this recipe that uses homemade mushroom soup.

1. Fried onions

As I mentioned before, I like to make my fried onions from scratch in lieu of grabbing a pack of store-bought onions. They take about 15 minutes to whip up and you can add so much more flavor and texture to the dish by making them from scratch.

an onion, bottle of buttermilk and a bowl of flour
You can use white, yellow, or sweet onions for this recipe.

Start by slicing your onions into very thin rounds.

If you have a mandolin, it would be a great tool to get nice, thin slices. I personally do not own one (partially because I am terrified of slicing my finger off) so I just use a sharp chef’s knife. My go-to knife for slicing is my Messermeister Oliva Stealth Chef’s Knife. It’s extremely sharp and has a great weight to it that allows me to fully control the thickness of my sliced onions.

sliced onion on a wooden chopping board

Once your onions are sliced, you want to let them soak in some buttermilk for about 10 minutes, but no longer than 30 minutes. The buttermilk will soften the onions and also act as the wet component of your light batter.

sliced onions in a bowl of buttermilk

While your onions are soaking, grab a small bowl and combine the flour, salt, pepper, garlic powder, and cayenne pepper. You can increase the amount of salt and pepper per your personal preference, but the key is to ensure that your flour is well-seasoned.

bowl onions in buttermil, bowl of flour, pot of oil on burner

After your onions have soaked for 10 minutes, just pull them out of the buttermilk and dredge them in the flour mixture until they are well-coated. Then drop them directly into 350°F oil to fry. I like to use vegetable oil for this recipe, but you can alternatively use canola oil or peanut oil, depending on what you have on hand.

They are going to take about 5 minutes to fry, but you don’t need to time it. Just watch them and when they turn a nice, golden-brown color they are ready to go.

deep fried onions on a white plate

Remove them from the oil with a slotted spoon and place them on a paper towel-lined plate. Set them off to the side and leave them on the counter while you prepare your green bean casserole.

2. Make the casserole

Green bean casserole is extremely easy to make and difficult to mess up, which is probably why it’s such a popular Thanksgiving side dish.

All you need to do is to combine the green beans, cream of mushroom soup, milk, soy sauce, and seasonings in a large casserole dish or aluminum tray. I like to use an aluminum tray because I already have enough dishes to wash on Thanksgiving and it saves me a little bit of time.

can of beans, can of mushroom soup, bottle soy saue, jug of milk
You can use fresh beans and home mushroom soup, check out my notes below.

Start by pouring the green beans into the dish, then add the cream of mushroom soup, milk, soy sauce, and seasonings. Mix it with a spoon until all of the ingredients are well combined and the green beans are fully coated in the sauce mixture.

uncooked green bean casserole in aluminum tray on the grill

Do not add the fried onions yet – you are going to wait until after it is almost fully cooked to top it with your fried onions.

3. Fire up the smoker

You can cook this recipe on any smoker or grill you prefer, as long as it can maintain a steady temperature of 350°F. I smoked this recipe on my Masterbuilt Gravity Series 1050 smoker. I love this grill for recipes like this because it has an internal fan that will maintain temperature with little-to-no effort on my part.

Fill the grill with your favorite lump charcoal – I used the B&B Charcoal Oak Lump for this recipe. I like Oak lump charcoal because it burns really evenly and provides a subtle smoky flavor that won’t overpower the dish.

cooked green bean casserole

Once your grill is up to temperature, you can place the green bean casserole directly on the grates.

Since most of the ingredients in this dish are pre-cooked, the cooking process does not take long. Let the casserole smoke for about 25 minutes, then add your fried onions on top and let it smoke for another 10 minutes and it’s ready to enjoy!

Once the green bean casserole is cooked, you can transfer it to your favorite serving dish and dig in!

green bean casserole on a spoon

What to serve with Smoked Green Bean Casserole?

Obviously, this casserole is the perfect side for your Thanksgiving dinner – here are some great Thanksgiving recipes to serve with your Smoked Green Bean Casserole:

smoked green bean casserole

Smoked Green Bean Casserole

5 from 3 votes
Classic green bean casserole with homemade fried onions and smoke!
PRINT RECIPE RATE RECIPE
Servings: 12
Prep Time20 minutes
Cook Time35 minutes
Total Time55 minutes

Ingredients 

Fried Onions

  • 2 onions - medium-sized
  • 1 pint buttermilk
  • 2 cups all purpose flour
  • ½ tbsp Kosher salt
  • 1 tbsp black pepper - course grind
  • 1 tsp garlic powder
  • ½ tsp cayenne pepper - optional
  • Vegetable oil - for deep frying

Smoked Green Bean Casserole

  • 4 cans cut green beans - 14.5oz cans
  • 2 cans cream of mushroom soup - 10.5oz cans
  • 1 cup whole milk
  • 1½ tbsp soy sauce
  • 1 tsp Kosher salt
  • 1 tsp black pepper - course grind
  • ½ tsp garlic powder
  • ½ tsp onion powder

Instructions

Fried Onions

  • Thinly slice your onions.
  • Transfer the sliced onions to a medium-sized bowl and pour the buttermilk over the top. Make sure the onions are fully-submerged and let them soak for 10 minutes (but not longer than 30 minutes).
  • In a medium sized bowl, combine the all-purpose flour, salt, pepper, garlic powder, and cayenne pepper.
  • Heat the vegetable oil in a pot over medium-high heat until it reaches 350°F.
  • Once the onions have soaked for 10 minutes, pull them out of the buttermilk and dredge them in the seasoned flour, then drop them in batches into the hot oil. Let them cook for about 5 minutes per batch until they reach a golden-brown color.
  • Remove the fried onions from the oil and transfer them to a paper towel lined plate to cool while you prepare your casserole.

Smoked Green Bean Casserole

  • Pre-heat your smoker to 350°F.
  • In a casserole dish or aluminum tray, combine the cut green beans, cream of mushroom soup, milk, soy sauce, and seasonings. Stir until well-combined and the green beans are fully coated.
  • Place your casserole directly on the grates of your smoker and let it smoke for 25 minutes.
  • Add the crispy fried onions all over the top of your casserole and let it continue to smoke for 10 more minutes until the onions are crispy and the casserole is slightly bubbly. Serve immediately.

Notes

Can I use fresh green beans? Yes! The trick if you want to use fresh green beans is to boil them for about 6 to 7 minutes before adding them to your casserole so that they are fully cooked in the final product.
Can I use homemade cream of mushroom soup? Yes! The key to using homemade cream of mushroom soup is to ensure that you mince your mushrooms into small pieces so that the size of the mushrooms doesn’t overpower the green beans.
Can I use the store-bought fried onions in this recipe? Yes! While I greatly prefer my homemade fried onions because they’re SUPER easy to whip up and more flavorful, the store-bought fried onions will work just fine. If you do choose to use the store-bought variety, I recommend adding about ½ cup of fried onions to the green bean mixture and then adding even more to the top.
Can I make this recipe in the oven instead? Of course, you can go the traditional route and make this recipe in the oven – but I prefer the smoker because it adds an extra layer of smoky flavor that really takes the dish up a notch. Plus, it saves room in the oven/kitchen for all of the other amazing Thanksgiving food that you are whipping up!
Can I prep this ahead of time? Yes! You can prep the green bean casserole up to 3 days in advance and store it in the fridge until you are ready to cook it. I recommend making the fried onions on the day of so they retain their crispy exterior, though.
What wood should I use to smoke it with? We used oak for this recipe. but any wood that provides a subtle smoky flavor that won’t overpower the dish would be suitable.

Nutrition

Calories: 129kcal | Carbohydrates: 22g | Protein: 6g | Fat: 2g | Saturated Fat: 1g | Polyunsaturated Fat: 0.2g | Monounsaturated Fat: 1g | Cholesterol: 6mg | Sodium: 585mg | Potassium: 265mg | Fiber: 2g | Sugar: 5g | Vitamin A: 501IU | Vitamin C: 8mg | Calcium: 87mg | Iron: 2mg

Nutrition information is automatically calculated and should be used as an approximation only. If you’re worried you could always add a side of kale.

Course: Side Dish
Cuisine: American
Fired up the smoker or grill for this one?We would love to hear how it turned out! Drop a comment and rate this recipe.
Breanna Stark, barbecue enthusiast, social media personality (@Marriedtobbq), and author at Smoked BBQ Source, smiling outdoors in a brown sweater sitting in front of a smoker.

About Your Pitmaster

Breanna Stark is a Texas-based competitive pitmaster and barbecue educator. She grew up cooking over charcoal and open flames while camping with her father, sparking a lifelong love of barbecue. Since 2014, she has competed in over 100 IBCA, KCBS, and CBA events, earning recognition for her award-winning chicken and Texas-style barbecue.

Passionate about recipe testing and development to create approachable dishes that help backyard cooks level up their barbecue skills. Breanna shares her expertise with over three million followers on social media.

See more posts by Breanna

5 from 3 votes (3 ratings without comment)

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