What's better than Shake Shack's Shroom Burger? This smoky, cheesy, melty, crunchy mushroom burger copycat on a housemade potato roll bun♡. No matter if you're a conscientious omnivore, a carnivore, or a full-fledged vegetarian, this easy mushroom burger will have you hooked without missing the meat at all!

There's a reason why this vegetarian burger is famous -- oven-roasted portobello mushrooms filled with piping-hot seasoned cheese and scallion filling, panko-crusted and fried to crispy, crunchy perfection. It's seriously delicious.

There's really only one question -- Would I go through all of the trouble to make this at home again? Or is there an easier way to get the same great taste without the extra effort? Keep reading to find out!

two portobello mushrooms halved horizontally and drizzled with extra virgin olive oil and sprinkled with freshly cracked black pepper and kosher salt on a sheetpan

the most beautifully golden brown squishy homemade potato roll hamburger buns with sesame and poppyseeds on top (5 total just baked)

What is Shake Shack's Shroom Burger?

We love Shake Shack. Their cheeseburgers are delicious, and so is their Shroom Burger. Portobello mushrooms get oven-roasted and stuffed with a blend of Muenster and cheddar cheese seasoned with minced onion and garlic (bound together with an egg yolk).

The stuffed mushrooms are then coated in panko bread crumbs and fried until crispy, and the cheese mixture has become a molten-lava center that you have to watch out for on your first bite or possibly get burned!

This vegetarian burger is so delicious that plenty of serious meat-eaters we know opt for it instead of the famous Shack Burger. What you'll find here is a very tasty twist on Shake Shack's Shroom burger in the form of a little extra smoky-scallion flavor.

It's pretty unforgettable, and you won't be thinking about not eating meat when you take your first (or last) bite!

If you love this burger, you might want to try this Crispy Shrimp Burger Recipe (Homemade Teochew Shrimp Patties) or this Extra Beefy Beyond Burger Recipe!

Jump to:

What is Shake Shack's Shroom Burger?
Copycat Shake Shack Shroom Burger Ingredients
How to Stuff Roasted Portobello Mushrooms + Fry Them
How to Make a Shake Shack Shroom Burger From Scratch Step-by-Step
How to Make a Shake Shack Shroom Burger The Easy Way
Looking for Easy Sandwich & Burger Recipes?
📖 Recipe

shroom burger raw ingredients all on a cutting board

Copycat Shake Shack Shroom Burger Ingredients

This is definitely one of the best vegetarian burger recipes out there. And there's no rule book that says you can't make meat-free burgers taste just as good as their beefy counterparts, which is what we've done here.

If you love the Shake Shack's Shroom Burger as much as we do, we think you'll love this version (maybe even more).

Oven-Roasted Portobello Ingredients

2 (4-inch) portobello mushrooms, sliced in half horizontally (through the middle)
2 tablespoons extra virgin olive oil (28g)
¼ teaspoon kosher salt (1.5g)
freshly cracked black pepper to taste

Cheese Stuffing Ingredients

¼ cup cheddar cheese, grated or diced (50g)
¾ cup provolone or Muenster cheese, grated or diced (125g)
1 large egg yolk (15g) *add the leftover egg white to the egg wash used in breading station
1 tablespoon scallions, minced (14g)
⅛ teaspoon all-purpose flour (.65g)
½ teaspoon smoked paprika (1.5g)
¼ teaspoon dried minced onion (.16g)
a pinch of dried minced garlic
a dash of kosher salt

Breading Station Ingredients

¾ cup all-purpose flour (100g)
1 cup Japanese Panko bread crumbs (60g)
2 eggs + 1 egg white (135g)
¼ cup portobello roasting juice (60g) *or save this juice for dipping your burger into au jus style

Kelly's Smoky Burger Sauce Ingredients *

¼ cup Hellman's or Duke's mayonnaise
2 tablespoons Heinz ketchup
2 to 3 teaspoons Heinz yellow mustard
½ teaspoon smoked paprika
1 teaspoon dill pickle brine
1 tablespoon finely diced dill pickles
¼ teaspoon cayenne pepper

(Use these measurements as a guideline only and adjust to your preferences)

How to Stuff Roasted Portobello Mushrooms + Fry Them

There's definitely an easier way to create this super delicious Fried Mushroom Burger Recipe, but for those of you looking for an authentic Shake Shack experience, this is what you'll have to do after roasting the portobellos.

cheddar and provolone diced with scallions and bound with egg yolk and ¼ teaspoon of flour formed into a round disc shape to put inside the mushroom

How to Make a Shake Shack Shroom Burger From Scratch Step-by-Step

If you love mushrooms, cheese, and fried things, this copycat Shake Shack Shroom Burger is for you. We punched it up with a smoky element that adds a little something extra. Short on time? Skip down to our easier method that delivers the same flavor with less mess.

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homemade smoky shack sauce with a small cornichon pickle to the left, shredded ice berg lettuce, and halved grape tomatoes

Step 1. Make the Biting at the Bits Smoky Burger Sauce. Combine all the sauce ingredients, adjust seasonings to your taste, and set aside.

drizzling EVOO onto portobello mushrooms

EVOO drizzled over a closeup of a horizontally sliced portobello mushroom

perfectly oven roasted portobello mushrooms sliced in half

Step 2. Preheat the oven to 375°F/190°C. Slice the mushrooms through the middle (horizontally), and place them on a baking pan. Drizzle with olive oil and rub the caps all over. Season with salt and pepper. Roast mushrooms for 30 to 35 minutes. Reserve the mushroom roasting juice, allow the mushrooms to cool, and then drain on paper towels.

breading station with egg wash, flour, and panko bread crumbs in separate bowls and containers

Step 3. Set up the breading station. Get out three medium bowls and place ¾ cups of flour in one, in another, beat 2 eggs plus the leftover egg white and ¼ cup of leftover mushroom juice from the roasted portobellos, and place the panko bread crumbs in a third bowl and set them aside.

finely diced provolone and cheddar cheese with green scallions, seasonings, and an egg yolk mixed in

cheese stuffed portobello mushroom in a bowl of flour

Step 4. Make the cheese filling. Add all of the cheese filling ingredients to a medium-sized bowl and stir to combine. Shape the filling into 2 equal-sized round mounds that are about ½-inch smaller than the diameter of the mushroom caps. Place the cheese mound directly in the center of each mushroom cap, enclosing the cheese mixture in between the mushroom halves.

Gently press the mushrooms together to "glue" them together. Place the mushrooms into the freezer for 10 minutes to allow them to firm up before coating them.

cheese stuffed portobello mushroom covered in flour and dusted off

cheese stuffed portobello mushroom covered in flour and dusted off and placed into egg wash

cheese stuffed portobello mushroom covered in flour and dusted off and covered in egg wash and placed into panko bread crumbs

my hand holding a panko-crusted cheese-stuffed portobello mushroom

Step 5. Coat the cheese-filled mushrooms with the breading. Dredge the stuffed mushroom caps in the flour; then coat them in the beaten egg, and then coat them in the panko bread crumbs. Set prepared mushrooms on a plate and refrigerate while heating the oil to deep-fry them.

super crunchy golden brown shroom burger just fried

Step 6. Fry the mushrooms. Add about 2 to 3 inches of neutral cooking oil to a deep pot or a deep fryer. Heat oil to 350° F/176°C and fry the mushrooms one or two at a time, until golden brown and crisp all over, turning over periodically for a total of about 3 or 4 minutes, or until golden brown. Remove mushrooms to a paper towel-lined plate and sprinkle with a little salt.

Step 7. Assemble the Shroom burger. Spoon the Smoky Burger Sauce onto the bottom buns, add lettuce and tomatoes, then the fried mushroom, and top it with more sauce and the top bun, enjoy!

a mushroom burger sliced in half being held in my hand with the cheese mixture oozing out

How to Make a Shake Shack Shroom Burger The Easy Way

Do you really have to stuff and fry the mushroom? No-and here's why I don't anymore.

After recreating the original stuffed version, my first bite confirmed what I suspected: you can get all that shroomy, cheesy, crunchy Shake Shack flavor without the extra work (*see exactly how below)

Skip the stuffing. Not having to stuff and chill the portobello caps shaves off significant prep time and mess. For busy home cooks, that's a win.

My verdict: I won't make the traditional stuffed version again. The easy method below delivers the same delicious result with half the effort.

How to Make This Shroom Burger the Easy Way

Slice, season, and roast the portobello mushrooms with salt, freshly cracked black pepper, and a drizzle of extra virgin olive oil.
Pat each mushroom slice dry and coat them with flour (that's been seasoned with a little garlic powder and onion powder), then dip them into egg, then panko bread crumbs, and fry them. Don't throw away the mushroom juice in the roasting pan (it's full of flavor and makes a perfect sauce for dipping the mushroom burger).
Toast the potato buns, add one slice each of provolone and cheddar cheese and a sprinkling of finely diced scallions to the bottom bun, and repeat with the top bun. Place the buns under the broiler just long enough to melt the cheese.
Build the mushroom burger by adding the hot slices of fried mushrooms, shack sauce, shredded lettuce, and anything else you want to add.