Why You’ll Love This Recipe

I love this recipe because it’s easy to prepare and packed with rich, savory flavor. The portobello mushrooms have a wonderfully meaty texture that makes this sandwich filling without relying on meat. I also enjoy how versatile it is, since I can customize the toppings, cheese, and sauces to create a new version every time I make it.

Ingredients

(Tip: You’ll find the full list of ingredients and measurements in the recipe card below.)

4 large portobello mushroom caps, stems removed
3 tablespoons olive oil
2 tablespoons balsamic vinegar
2 cloves garlic, minced
1 teaspoon Dijon mustard
1 teaspoon Italian seasoning
1/2 teaspoon salt
1/4 teaspoon black pepper
4 sandwich buns or brioche buns
4 slices provolone, Swiss, or mozzarella cheese (optional)
4 lettuce leaves
1 large tomato, sliced
1 small red onion, thinly sliced
Sliced avocado (optional)
Mayonnaise, pesto, or garlic aioli, for spreading

Directions

I whisk together the olive oil, balsamic vinegar, garlic, Dijon mustard, Italian seasoning, salt, and black pepper to make the marinade.
I brush the marinade generously over both sides of the portobello mushrooms and let them marinate for about 15 to 20 minutes.
I preheat a grill, grill pan, or oven to medium-high heat.
I cook the mushrooms for about 5 to 7 minutes per side until they are tender and juicy.
I place a slice of cheese on each mushroom during the last minute of cooking if I’m using cheese.
I lightly toast the sandwich buns until golden.
I spread mayonnaise, pesto, or garlic aioli on the buns.
I layer the lettuce, grilled mushroom, tomato, red onion, and avocado on the bottom bun.
I top with the remaining half of the bun and serve immediately.

Servings and Timing

Servings: 4
Prep Time: 20 minutes
Cook Time: 15 minutes
Total Time: 35 minutes

Variations

I add roasted red peppers for a sweet, smoky flavor.
I top the sandwich with caramelized onions for extra richness.
I use goat cheese or feta instead of provolone for a tangy twist.
I add fresh spinach or arugula instead of lettuce.
I spread hummus on the bun for a Mediterranean-inspired version.
I include grilled zucchini or eggplant for an even heartier vegetable sandwich.

Storage/Reheating

I store the cooked mushrooms separately from the buns and fresh toppings in airtight containers in the refrigerator for up to 3 days. When I’m ready to enjoy them again, I reheat the mushrooms in a skillet over medium heat, in a 350°F (175°C) oven for about 8 minutes, or in the microwave until warmed through. I assemble the sandwich just before serving to keep the vegetables crisp and the bread fresh.

FAQs

Can I make this sandwich vegan?

Yes. I simply skip the cheese or use a dairy-free alternative, and I spread vegan mayonnaise or hummus on the buns.

How do I keep the mushrooms from becoming watery?

I avoid soaking the mushrooms when cleaning them and cook them over medium-high heat so excess moisture evaporates quickly.

Can I cook the mushrooms in an air fryer?

Yes. I air fry the marinated mushrooms at 375°F (190°C) for about 10 to 12 minutes, flipping them halfway through cooking.

What bread works best for a Portobello Mushroom Sandwich?

I enjoy using brioche buns, ciabatta rolls, sourdough, or whole wheat sandwich buns because they hold the juicy mushrooms well.

What side dishes pair well with this sandwich?

I like serving it with sweet potato fries, roasted potatoes, a green salad, coleslaw, grilled vegetables, or a cup of tomato soup.

Conclusion

I always enjoy making this Portobello Mushroom Sandwich because it’s flavorful, satisfying, and incredibly easy to prepare. The marinated mushrooms create a hearty centerpiece, while the fresh vegetables and creamy spread bring everything together. Whether I’m looking for a quick weeknight dinner or a delicious vegetarian lunch, this sandwich is one of my favorite recipes to make again and again.

Portobello Mushroom Sandwich Recipe

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This Portobello Mushroom Sandwich is a hearty meatless meal featuring juicy, marinated mushrooms, fresh vegetables, and your choice of creamy spread on a toasted bun. It’s flavorful, satisfying, and perfect for lunch or a simple dinner.

Author: Laura
Prep Time: 20 minutes
Cook Time: 15 minutes
Total Time: 35 minutes
Yield: 4 servings
Category: Main Course
Method: Grill
Cuisine: American
Diet: Vegetarian

Instructions

Whisk together the olive oil, balsamic vinegar, garlic, Dijon mustard, Italian seasoning, salt, and black pepper to make the marinade.
Brush the marinade generously over both sides of the portobello mushrooms and let them marinate for 15 to 20 minutes.
Preheat a grill, grill pan, or oven to medium-high heat.
Cook the mushrooms for 5 to 7 minutes per side until tender and juicy.
Place a slice of cheese on each mushroom during the last minute of cooking if using cheese.
Lightly toast the sandwich buns until golden.
Spread mayonnaise, pesto, or garlic aioli on the buns.
Layer the lettuce, grilled mushroom, tomato, red onion, and avocado on the bottom bun.
Top with the remaining bun and serve immediately.

Notes

Use vegan cheese and vegan mayonnaise or hummus for a vegan-friendly version.
Add roasted red peppers or caramelized onions for extra flavor.
Swap lettuce for spinach or arugula for a peppery bite.
Store cooked mushrooms separately from buns and fresh toppings for up to 3 days in the refrigerator.
Reheat mushrooms in a skillet, oven, or air fryer before assembling the sandwiches.

Nutrition

Serving Size: 1 sandwich
Calories: 460 kcal
Sugar: 7 g
Sodium: 620 mg
Fat: 24 g
Saturated Fat: 6 g
Unsaturated Fat: 16 g
Trans Fat: 0 g
Carbohydrates: 43 g
Fiber: 5 g
Protein: 16 g
Cholesterol: 20 mg