Marinated Portobello Mushroom Sandwich with Grilled Bell Pepper

Marinated Portobello Mushroom Sandwich with Grilled Bell Pepper, gruyere cheese and mozzarella cheese

Marinated Portobello Mushroom Sandwich, served on a whole grain bread with grilled bell pepper, melted gruyere cheese, and mozzarella. To make this roasted portobello sandwich, I marinated the mushrooms in a balsamic vinegar oil mixture for at least 15 minutes then cook in the oven for about 10-15 minutes until they become tender. 

Marinated Portobello Mushroom Sandwich with Grilled Bell Pepper, gruyere cheese and mozzarella cheese
The cooking process of this roasted portobello sandwich is pretty simple.  I managed to grill the bell peppers at the same time that I roasted the portobello mushrooms in the oven. What makes this marinated portobello mushroom sandwich great?  It’s all about the balance of the crunch of the buttered bread with the melty, gooey and the nutty flavor of the gruyere cheese. It literally melted in my mouth, so delicious!  If you can’t find the gruyere cheese at your local store, you can use Manchego, Gouda, or a mild cheddar as an alternative. Also, check out one of our most favorited sandwich recipe: Eggplant Panini with Balsamic Sun-Dried Tomatoes

Marinated Portobello Mushroom Sandwich with Grilled Bell Pepper, gruyere cheese and mozzarella cheese

To prepare the portobello mushroom before cooking, simply remove the stems, scrape out the gills with a spoon if you prefer, and use a damp paper towel to wipe each side of mushroom to remove any dirt. You can repeat this step to make sure that the mushroom is fully cleaned. Do not soak the mushrooms because they can absorb all the liquid quickly and reduce the flavor.

Marinated Portobello Mushroom Sandwich with Grilled Bell Pepper Recipe:

5 from 2 votes
Marinated Portobello Mushroom Sandwich with Grilled Bell Pepper, Melted Gruyere cheese, and Mozzarella.

Servings: 2 people
Marinated Portobello Mushrooms:
  • 2 Portobello Mushrooms
  • 1/4 cup Olive oil
  • salt/pepper to taste
  • 4 garlic cloves , minced
  • 4 tablespoons balsamic vinegar
  • 1 teaspoon onion powder
  • optional: a pinch of thyme leaves
Grilled Bell Pepper:
  • 1 Red Bell Pepper
  • 1 Green Bell Pepper
  • 1 tablespoon olive oil
  • 1/2 teaspoon balsamic vinegar
  • sea salt/black pepper
  • optional: a pinch of dried basil or slivered fresh basil
To Assemble Sandwich:
  • 4 slices sourdough
  • 1 tablespoon salted butter
  • Guyerre cheese
  • Mozzarella cheese
Roasted Portobello Mushrooms:
  1. In a large mixing bowl, combine olive oil, salt/pepper to taste, garlic, balsamic vinegar, onion powder and thyme leaves.

  2. Clean mushrooms and remove stems. Wipe them with a damp cloth.

  3. Marinate the mushroom in an olive oil mixture for at least 15 minutes.

  4. Preheat the oven to 400°.

  5. Place the mushrooms on a baking sheet.

  6. Roast for about 10-15 minutes or until tender.
Grilled Bell Pepper:
  1. In a mixing bowl, mix together bell pepper, olive oil, balsamic, sea salt/black pepper, basil.

  2. Place the bell pepper on a grill over medium heat and cook for about 8-10 minutes or until crisp tender and until the skin is completely charred.

  3. Remove the bell pepper from the heat, when cooled, remove the charred skin. Cut into small pieces and remove seeds. Optional: add salt/pepper according to your liking.
To Assemble the sandwich:
  1. Assemble the sandwich with a slice of bread, a slice of Gruyere cheese, chopped portobello mushrooms, grilled bell pepper, a slice of Mozzarella cheese and another slice of bread.

  2. In a cast iron or non-stick skillet over medium low heat, heat 1 tablespoon salted butter.

  3. Place the sourdough sandwich in a skillet, press slightly until golden, flip carefully, add more butter if needed, cook the other side until golden and the cheese melts for about 3-4 minutes.

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  • Reply
    Aug 3, 2017 at 2:08 pm

    I really want to have this sandwich now!!! So flavourful and delicious.

  • Reply
    Aug 3, 2017 at 3:08 pm

    I love vegetarian sandwiches like this! It would be delicious in a panini press!

  • Reply
    Ginny McMeans
    Aug 3, 2017 at 4:10 pm

    Yes! I want this sandwich. I could have some sort of sandwich for every meal if ‘they’d’ let me. 🙂 The flavors sound like a perfect combo.

  • Reply
    Annemarie @ justalittlebitofbacon
    Aug 3, 2017 at 5:27 pm

    This looks like a great, vegetarian meal! I love the melty cheese and all the roasted/grilled veggies.

  • Reply
    Sarah @ Champagne Tastes
    Aug 3, 2017 at 5:38 pm

    I love roasted portobellos! This sounds delicious- I need to make more veggie sandwiches!

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