Introduction

This Best Portobello Mushroom Burger recipe offers a juicy, flavorful alternative to traditional burgers. Grilled to perfection and topped with melted Brie and a zesty pesto mayo, it’s a satisfying meal for mushroom lovers and vegetarians alike.

Best Portobello Mushroom Burger Recipe - Recipe Image

Ingredients

4 portobello mushroom caps
¼ cup olive oil
2 Tbsp. lemon juice
1 garlic clove, minced
¼ tsp. salt
¼ tsp. pepper
3 Tbsp. mayonnaise
1 Tbsp. pesto, store-bought or homemade
4 oz. Brie cheese
4 hamburger buns

Instructions

Step 1: Trim the stem off each portobello mushroom and wipe away any dirt with a wet paper towel.
Step 2: In a bowl, combine olive oil, lemon juice, minced garlic, salt, and pepper. Place mushrooms gill-side down on a plate and brush them lightly with the olive oil mixture. Flip mushrooms and brush the gill side with the remaining mixture. Let them marinate for 10 minutes.
Step 3: Preheat your grill to medium heat. Place mushrooms gill side up on the grill and cook until grill marks appear underneath, approximately 4 minutes. Turn the mushrooms 90° to create crosshatch grill marks and cook for another 2 minutes. Flip mushrooms and repeat the crosshatch grilling on this side.
Step 4: Flip the mushrooms again and place 1 ounce of Brie cheese on each mushroom cap. Allow the cheese to melt slightly, then remove the mushrooms from the grill and transfer to a plate.
Step 5: In a small bowl, mix mayonnaise and pesto together. Spread about 1 tablespoon of this mixture on the top and bottom halves of each hamburger bun. Assemble burgers by placing the mushroom caps on the buns and adding your favorite toppings as desired.

Tips & Variations

For extra smoky flavor, add a splash of balsamic vinegar to the marinade.
Use a grill pan if you don’t have an outdoor grill, and cook on medium-high heat for similar results.
Swap Brie for mozzarella or goat cheese for a different creamy texture.
Add fresh arugula, tomato slices, or caramelized onions to enhance the burger toppings.

Storage

Store any leftover grilled portobello mushrooms in an airtight container in the refrigerator for up to 3 days. To reheat, warm them gently in a skillet over medium heat or briefly in the microwave until heated through. It’s best to assemble the burgers fresh before serving.

How to Serve

Serve this delicious recipe with your favorite sides.

FAQs

Can I make this burger vegan?

Yes! Simply substitute the Brie cheese with a vegan cheese alternative and use vegan mayonnaise to keep the pesto mayo vegan-friendly.

What is the best way to clean portobello mushrooms?

Use a damp paper towel or a soft brush to gently wipe dirt off the mushroom caps. Avoid rinsing them under water to prevent sogginess.

Best Portobello Mushroom Burger Recipe

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4.6 from 117 reviews

This Best Portobello Mushroom Burger recipe offers a flavorful, vegetarian alternative to traditional burgers. Juicy, marinated portobello mushrooms are grilled to perfection, topped with melted Brie cheese, and layered on a bun with a zesty pesto-mayo spread. Easy to prepare and packed with robust flavors, it’s an ideal dish for a satisfying meatless meal.

Author: Isabella
Prep Time: 15 minutes
Cook Time: 12 minutes
Total Time: 27 minutes
Yield: 4 servings 1x
Category: Main Course
Method: Grilling
Cuisine: American
Diet: Vegetarian

Ingredients

Scale

Mushroom Marinade

4 portobello mushroom caps
¼ cup olive oil
2 Tbsp. lemon juice
1 garlic clove, minced
¼ tsp. salt
¼ tsp. pepper

Spread

3 Tbsp. mayonnaise
1 Tbsp. pesto (store-bought or homemade)

Cheese & Assembly

4 oz. Brie cheese
4 hamburger buns

Instructions

Prepare Mushrooms: Trim the stems off the portobello mushrooms and gently wipe any dirt off using a wet paper towel to keep them clean without soaking them.
Marinate Mushrooms: In a bowl, mix together olive oil, lemon juice, minced garlic, salt, and pepper. Place the mushrooms gill-side down on a plate and brush lightly with the olive oil mixture. Flip them over and coat the gill side with the remaining marinade. Let them sit for 10 minutes to absorb the flavors.
Preheat Grill: Heat your grill to medium heat to prepare for cooking the mushrooms evenly and to get nice grill marks.
Grill Mushrooms: Place the mushrooms gill side up on the grill. Cook until you see attractive grill marks underneath, about four minutes. Turn each mushroom 90 degrees to create crosshatch grill marks and cook for an additional two minutes. Flip the mushrooms and repeat the process on the other side. Then flip the mushrooms again and place 1 ounce of Brie cheese on top of each mushroom, allowing it to melt as they finish cooking. Once the cheese has melted, remove the mushrooms from the grill and place on a plate.
Prepare Spread & Assemble Burger: In a small bowl, combine the mayonnaise and pesto until smooth. Spread about 1 tablespoon of this mixture onto each hamburger bun. Place the grilled Brie-topped mushroom on the bun and add your favorite burger toppings as desired. Serve immediately while warm.

Notes

For a vegan version, substitute mayonnaise and Brie with plant-based alternatives.
Make sure to not soak mushrooms in water, as they absorb moisture easily and can become soggy.
Use a grill pan if you don’t have access to an outdoor grill.
Feel free to customize toppings like lettuce, tomato, or avocado for extra freshness.
If you prefer stronger flavor, marinate mushrooms longer, up to 30 minutes.

Keywords: Portobello mushroom burger, grilled mushroom burger, vegetarian burger, Brie cheese burger, pesto mayonnaise spread