Author: Catherine McCord

Why You’ll Love This Recipe

• Flavor Explosion: The panko coated, crispy-fried portobello mushroom gives a satisfying crunch, but the absolute best part is the explosion of melty cheese you get after you take your first bite.
• Perfect for Vegetarians: This vegetarian burger is a hearty, satisfying burger that both vegetarians and meat-eaters will love! I guarantee it. Pair these with Air Fryer French Fries for the perfect dinner combo!
• Easy to Customize: You can make these shroom burgers your own by adding your favorite toppings and sauces just like you would any regular beef burger. Our favorites are lettuce, tomato and some avocado slices.
• Shake Shack at Home: My vegetarian son recreated his favorite Shake Shack burger – the Shroom Burger – for a family cook-off one year, and it turned out amazing! Now we get to enjoy the iconic taste of Shake Shack at home whenever we want. P.S. Don’t forget the homemade ShackSauce (recipe below)!

The Ingredients

For the Shroom Burgers:

• Portobello mushroom caps: Portobello mushrooms have a meaty, dense texture that holds up well in cooking. Their flavor is rich, earthy, and slightly umami, making them a satisfying substitute for meat in many recipes like these burgers.
• Oil: Any high smoke point oil (olive, avocado, vegetable or canola oil) will work for shallow frying these shroom burgers. 
• All purpose flour: The flour provides a dry surface that helps the egg adhere better to the burger during the breading process. Without the flour, the egg might slide off the mushroom’s slick surface.
• Large eggs: Eggs serve as a binding agent, helping the breadcrumbs stick to the burgers to create a thicker and more even coating. They’re also used in the cheese filling to help it stick together.
• Panko breadcrumbs: Coating the mushrooms in panko gives the shroom burgers their irresistible crispy, crunchy and golden brown exterior.
• Mozzarella & cheddar cheese: Ooey gooey cheese in the center of every shroom burger creates a melty cheese explosion you’ll love.
• Onion powder, garlic powder & salt: These seasonings are mixed with the cheese mixture to add extra flavor to the burgers.

For the Faux ShackSauce:

• Mayonnaise (or vegan mayonnaise): This creamy base gives the sauce its rich and smooth texture.
• Dijon Mustard: Adds a tangy, slightly spicy flavor that enhances the sauce’s complexity.
• Ketchup: Brings a touch of sweetness and tomato flavor to balance the tanginess.
• Dill Pickle Juice: Pour straight from your jar of pickles in the refrigerator for a zesty, briny kick.

*For a full list of ingredients and instructions see the recipe card below*

How to Make Shroom Burgers

Step 1: Preheat oven to 375°F. Place the mushrooms on a parchment lined baking sheet, rub with oil and sprinkle with salt on both sides. Place mushrooms gill side down and roast for 30-35 minutes or until slightly golden. Remove from oven and allow to cool. 

Step 2: Slice the mushroom caps horizontally being careful to make sure to cut directly through so both sides are even. 

Step 3: For the cheese filling, place the cheeses, onion and garlic powder and one egg in a medium sized bowl and stir to throughly combine. Form the mixture into 4 even sized disks just smaller than the mushrooms. Place a disk of the cheese in between each mushroom to create a sandwich and press to secure. Refrigerate until ready to use.

Step 4: Create a breading station. Place the flour in a deep bowl or pie plate. Whisk 3 of the eggs in a similar sized bowl and the panko in a third bowl.

Step 5: Dredge each stuffed mushroom in the flour, then the whisked eggs and finally coating with the panko, pressing to adhere.

Step 6: Heat a large sauté or cast-iron pan with 1/2 inch of oil over medium high heat (if using a candy thermometer it should read 350 degrees). Fry the burgers on each side for 3-4 minutes or until golden and crisp. Transfer the burgers to a paper towel lined plate to remove excess oil.

Step 7: Make the faux ShackSauce. Place the sauce ingredients in a bowl and stir to combine.

Step 8: Place a shroom burger on the bottom a bun, top with avocado slices, tomato, lettuce and ShackSauce (if desired) add the top bun.

Shroom Burger Tips & Tricks

• Oil Temperature: Ensure your oil is hot enough before frying to get that perfect crispy coating without soaking up too much oil.
• Refrigerate The Cheese-Stuffed Mushrooms: Once you build the mushroom patties with the cheese filling, pop them in the refrigerator for a bit before breading.
• Tips for Making Ahead of Time
  • Portobellos can be roasted up to 3 days ahead of time and stored in the refrigerator. Slice when ready to fill and cook.
  • The breaded burger patties can be and stored in the refrigerator for 24 hours and then cooked as instructed.

FAQs