Portobello Mushroom Burger with Mozzarella, Roasted Peppers and Pesto Mayo Recipe

If you’re craving a hearty, flavor-packed vegetarian option that absolutely doesn’t skimp on satisfaction, this Portobello Mushroom Burger with Mozzarella, Roasted Peppers and Pesto Mayo was made for you. Imagine juicy grilled mushrooms stacked with creamy mozzarella, sweet roasted peppers, and a slather of herby pesto mayo — all nestled in a golden toasted bun. This is the kind of burger that will have you swooning at first bite!

this …

Ingredients You’ll Need

Let’s talk about how beautifully simple these ingredients are: each one plays a starring role! From meaty portobello caps to silky mozzarella, every element in the Portobello Mushroom Burger with Mozzarella, Roasted Peppers and Pesto Mayo brings a burst of flavor, texture, or gorgeous color — and best of all, you can find everything at your local supermarket.

• Portobello mushroom caps: The bold, meaty “patties” that soak up all that delicious marinade while offering a fantastic burger-like bite.
• Fresh mozzarella cheese: Sliced thin so it melts gently over the hot mushrooms, adding creaminess and mild flavor.
• Roasted red pepper (jarred or homemade): Brings sweetness, vibrant color, and a silky, tender texture — plus, it pairs beautifully with pesto and cheese.
• Pesto: Store-bought works in a pinch, but homemade pesto gives that ultra-fresh basil and garlic punch.
• Light mayo: Creamy and tangy, it mellows the pesto into a luscious, spreadable sauce for your buns.
• Balsamic vinegar: For a sweet-acidic note in the mushroom marinade — it makes everything pop!
• Low sodium soy sauce: Adds depth and a subtle saltiness to the marinade.
• Olive oil: Helps carry flavors and prevents the mushrooms from sticking to the grill.
• Montreal Steak Seasoning: That little bit of classic spice blend works wonders on mushrooms, giving a savory boost.
• Thick red onion slices: Grill them for extra sweetness and crunch; they turn mild and almost jammy.
• Whole wheat low calorie buns: Toasted for just a touch of crunch and a nutty, wholesome base for all those juicy toppings.

Variations

Don’t be afraid to make this Portobello Mushroom Burger with Mozzarella, Roasted Peppers and Pesto Mayo your own! It’s super adaptable, so feel free to swap in favorite cheeses, sauces, or buns to fit your mood or dietary needs. Here are a few fun twists to get you started:

• Vegan-Friendly: Use vegan mozzarella and your favorite vegan mayo and pesto for a completely plant-based burger that’s still packed with flavor.
• Spicy Kick: Add a few rings of pickled jalapeño, a smear of Calabrian chili, or spicy arugula for some heat and zing.
• Gluten-Free Option: Swap the whole wheat buns for gluten-free burger buns or serve “naked” mushroom stacks over greens.
• Cheese Swap: Try provolone, smoked gouda, or even pepper jack for a flavorful spin!

How to Make Portobello Mushroom Burger with Mozzarella, Roasted Peppers and Pesto Mayo

Step 1: Mix the Pesto Mayo

Start by combining your pesto and light mayo in a small bowl. This creamy, herby spread comes together in seconds and elevates the burger with every bite. Trust me, you’ll want to make extra for dipping fries or spreading on future sandwiches!

Step 2: Marinate the Portobellos

In a large bowl, whisk together the balsamic vinegar, soy sauce, olive oil, and Montreal steak seasoning. Add your cleaned portobello mushroom caps and toss well to coat, spooning the marinade over so every surface soaks it up. Let the mushrooms sit at room temperature for 20–30 minutes, turning them a few times to ensure they soak evenly. This is where all that mouthwatering flavor develops!

Step 3: Heat Up the Grill

Get your grill or grill pan preheating over medium heat. Once it’s hot, brush the grill grate with a little oil (or spray your pan), then get ready for some sizzle.

Step 4: Grill the Mushrooms, Onions, and Buns

Place the marinated mushrooms on the grill, reserving the leftover marinade for basting. Cook them for 5–7 minutes per side, brushing with marinade every few minutes until they’re juicy and tender. During the last minute of cooking, top each mushroom with mozzarella so it melts into gooey perfection. Pop the onion slices on the grill (about a minute per side) and toast your buns until golden.

Step 5: Assemble Your Burger

Generously spread the pesto mayo over the toasted buns. Layer on a cheesy mushroom, then top with grilled onion rings and sweet roasted peppers. Cap it off with the other bun half, grab some napkins, and savor every glorious layer of your Portobello Mushroom Burger with Mozzarella, Roasted Peppers and Pesto Mayo!

How to Serve Portobello Mushroom Burger with Mozzarella, Roasted Peppers and Pesto Mayo

Garnishes

Brighten up your burger with a handful of fresh basil leaves, a quick grind of black pepper, or even a sprinkle of flaky sea salt just before serving. A little drizzle of extra pesto or balsamic glaze will make every bite even more delectable!

Side Dishes

This burger loves company! Try serving it alongside homemade sweet potato fries, a crisp green salad tossed with lemon vinaigrette, or even marinated tomato salad. If you’d really like to lean in, oven-roasted potato wedges or grilled corn on the cob are fantastic too.

Creative Ways to Present

Go mini by making slider versions for a party tray, or deconstruct your Portobello Mushroom Burger with Mozzarella, Roasted Peppers and Pesto Mayo into a beautiful grain bowl over quinoa with extra veggies. You can also assemble them open-faced for an elegant knife-and-fork dinner!

Make Ahead and Storage

Storing Leftovers

If you find yourself with extra burgers (a rare but happy problem!), store the mushrooms, onions, and peppers separately from the buns and pesto mayo. Keep everything in airtight containers in the fridge, and they’ll stay delicious for up to three days.

Freezing

You can freeze the grilled portobello mushrooms individually wrapped in foil or parchment, then stored in a freezer bag for up to two months. For best results, thaw overnight in the fridge before reheating — but skip freezing the cheese or veggies, as their texture is best when freshly made.

Reheating

To reheat, warm the mushrooms gently in a skillet over medium-low heat or on a baking sheet in a 350°F oven until heated through. Add fresh cheese and toppings just before serving to recapture that melty, lively texture and flavor!

FAQs

Final Thoughts

If you’re searching for a dinner that’s colorful, satisfyingly “meaty,” and bursting with Mediterranean-inspired flavor, you will adore this Portobello Mushroom Burger with Mozzarella, Roasted Peppers and Pesto Mayo. Gather your ingredients, fire up your grill, and treat yourself — I promise, your tastebuds (and friends!) will thank you.

Print