If you’re on the hunt for a vegetarian burger that’s bursting with flavor and downright satisfying, you’ve got to try this Marinated Portobello Mushroom Burgers Recipe. These grilled mushrooms soak up a savory marinade that makes every bite juicy and delicious—trust me, they’re a total crowd-pleaser!

A close-up view of a sandwich held by a woman's hand, made with a soft golden top bun. Inside, from bottom to top, there is a layer of fresh green leafy arugula, a juicy dark brown grilled patty topped with melted light yellow cheese, a slice of ripe red tomato, thick rings of purple onion, and sliced green pickles. Creamy orange sauce drips slightly down from the top bun. The background is dark and blurred, with the sandwich as the clear focus. photo taken with an iphone --ar 2:3 --v 7

Jump to:

Why You'll Love This Recipe
Ingredients & Why They Work
Make It Your Way
Step-by-Step: How I Make Marinated Portobello Mushroom Burgers Recipe
Top Tip
How to Serve Marinated Portobello Mushroom Burgers Recipe
Make Ahead and Storage
Frequently Asked Questions:
Final Thoughts
Marinated Portobello Mushroom Burgers Recipe

Why You'll Love This Recipe

I’ve been making these marinated portobello mushroom burgers for friends and family for years, and every time someone takes a bite, there’s this moment of surprise—they can’t believe how meaty and flavorful a mushroom can be. It’s a quick way to satisfy your burger craving without meat.

Rich, Smoky Flavor: The marinade has a perfect blend of smoky paprika and soy sauce that brings the mushrooms to life.
Simple Ingredients: You probably already have most of what you need in your pantry.
Quick to Prepare: The mushrooms soak up flavor in just 30 minutes of marinating, then only 15 minutes on the grill.
Perfect for Summer: Grilling these burgers outdoors is a fun way to elevate your weekday dinners or weekend cookouts.

Ingredients & Why They Work

When shopping for this recipe, aim for fresh, firm portobello caps that are about half a pound total—these are ideal for burger-sized portions. The magic truly happens with the marinade ingredients, which balance savory, sweet, and smoky perfectly, so stock up on quality spices and condiments.

Flat lay of fresh whole portobello mushroom caps with dark brown gills visible, two soft golden hamburger buns, a small mound of vibrant green spring mix leaves, one ripe red tomato sliced in half showing juicy interior, thin rings of crisp purple-red onion, a small white ceramic bowl of smooth pale mayonnaise, a small white ceramic bowl with golden olive oil, a small white ceramic bowl of dark soy sauce, a small white ceramic bowl of amber apple cider vinegar, a small white ceramic bowl of light brown granulated brown sugar, a small white ceramic bowl containing dried oregano leaves, a small white ceramic bowl of fine garlic powder, a small white ceramic bowl of fine onion powder, a small white ceramic bowl of deep red smoked paprika powder, and a small white ceramic bowl holding freshly cracked black peppercorns—all arranged symmetrically on a clean white marble surface, soft natural light, photo taken with an iPhone, professional food photography style, fresh ingredients, white ceramic bowls, no bottles, no duplicates, no utensils, no packaging --ar 2:3 --v 7 --p m7354615311229779997

Olive oil: Helps carry flavors and keeps the mushrooms tender during grilling.
Soy sauce: Adds an umami depth and saltiness that makes the mushrooms taste hearty.
Apple cider vinegar: Offers a subtle tang that brightens the marinade.
Brown sugar: Balances the acidic and savory notes with a touch of sweetness.
Oregano: A classic herb that pairs beautifully with mushrooms.
Garlic powder: Adds a gentle garlic punch without overpowering.
Onion powder: Gives a mild savory backbone to the marinade.
Smoked paprika: Brings that lovely smoky dimension without needing a smoker.
Freshly cracked pepper: Just a pinch to enhance flavors and add a little kick.
Portobello mushroom caps: The star of the show—meaty, juicy, and perfect for grilling.
Buns: Choose your favorite type—whole wheat, brioche, or classic hamburger buns all work.
Optional toppings: Spring mix, juicy tomato slices, rings of red onion, and creamy mayonnaise brighten and complete each bite.

📝

Note: You'll find the complete list of ingredients, along with their exact measurements, in the printable recipe card at the bottom of this post.

Make It Your Way

One of the best parts about this Marinated Portobello Mushroom Burgers Recipe is how easy it is to tailor to your own taste buds. Whether you love bold smoky flavors or prefer a lighter touch, there’s room to make these burgers truly your own.

Variation: I like to add some melted provolone or mozzarella cheese on top of the mushrooms during the last minute of grilling for a gooey finish that pairs beautifully with the smoky marinade.
Vegan option: Swap out the mayonnaise for a plant-based spread to keep it fully vegan without sacrificing creaminess.
Extra smoky: Adding a pinch of smoked salt or an extra dash of smoked paprika amps up the flavor, giving the mushrooms a deeper, campfire-inspired character.
Seasonal twist: Try topping with grilled peaches or caramelized onions in late summer for a sweet contrast that brightens the savory notes.

Step-by-Step: How I Make Marinated Portobello Mushroom Burgers Recipe

The image shows a white plate with a veggie burger open-faced. The bottom bun is topped with fresh green lettuce, then a thick, dark brown grilled portobello mushroom patty with visible grill marks sits on top. Above the patty are two bright red tomato slices and two rings of purple-red onion. The top bun lies open on the side, spread with a smooth light cream sauce. On the left side of the plate, there is a small pile of seasoned golden-brown potato chips. In the background, there is a wooden board with extra sliced red onions and tomato, and a small wooden bowl with more cream sauce, all set on a white marbled surface. Photo taken with an iphone --ar 2:3 --v 7

Step 1: Whisk Together the Flavor-Packed Marinade

Start by combining 2 tablespoons olive oil, 2 tablespoons soy sauce, 1 tablespoon apple cider vinegar, 1 teaspoon brown sugar, ¼ teaspoon each of oregano, garlic powder, onion powder, and 1 teaspoon smoked paprika, plus about 10 cranks of freshly cracked black pepper in a small bowl. Stir everything until the brown sugar dissolves and the marinade looks nice and uniform. This mixture is the heart of your burger’s bold, smoky-salty flavor.

Step 2: Marinate the Mushrooms — The Key to Juicy Flavor

Remove the stems from 2 portobello mushroom caps, then place them gill-side up in a shallow dish. Pour some marinade into the gills to really soak in the flavors, then flip the mushrooms over and pour the remaining marinade on top. Let them rest and soak for 30 minutes, flipping occasionally to make sure every inch gets coated. The marinating time is essential—it transforms the mushrooms from bland to beautifully seasoned and ensures they stay juicy when grilled.

Step 3: Grill the Mushrooms for Perfect Tenderness

Heat your grill or grill pan to medium to medium-high heat. Once it’s nice and hot, lay the mushrooms down and cook them for about 7 minutes on each side. You’ll notice the mushrooms releasing their liquid and softening beautifully. The goal is tender mushrooms with a slight char and that smoky essence from the marinade. Avoid overcrowding the grill to ensure even cooking. When done, let them rest for a couple of minutes to lock in their juiciness.

Step 4: Assemble Your Ultimate Portobello Mushroom Burgers

Place each perfectly grilled mushroom cap on a bun and dress it up with your favorite toppings. I love layering on mayonnaise, fresh tomato slices, crisp red onion rings, and a handful of peppery spring mix. This combo adds freshness and texture that beautifully balances the rich, smoky mushrooms. Serve immediately to enjoy all the flavors at their best.

Top Tip

These tips will help you elevate your Marinated Portobello Mushroom Burgers Recipe to the next level, making your cooking experience smoother and your result even more delicious.

Marinating Time Matters: Allow those mushrooms the full 30 minutes to soak up all the bold, smoky, and slightly sweet flavors — it's worth the wait for that deep, savory taste.
Don’t Skip the Rest: After grilling, let your mushrooms rest for a couple of minutes. This little pause keeps them juicy and tender when you bite in.
Grill with Space: Make sure not to overcrowd the grill or pan — giving mushrooms enough room means they’ll sear beautifully and cook evenly, rather than steaming.
Save Those Stems: I always chop up the mushroom stems for an omelette or toss them in my veggie stock stash — zero waste and extra flavor!

How to Serve Marinated Portobello Mushroom Burgers Recipe

In a white rectangular baking dish, there are two large, dark brown cooked mushrooms sitting in a shallow pool of golden brown liquid with some darker specks around the edges. The mushrooms have a slightly wrinkled texture and a rich, glossy look from the sauce. The white marbled surface beneath the dish adds a clean contrast to the warm colors of the mushrooms and sauce. photo taken with an iphone --ar 2:3 --v 7

Garnishes

Classic toppings like fresh spring mix, juicy tomato slices, and crisp red onion rings complement the smoky, tender mushrooms perfectly. A dollop of mayonnaise (or a vegan spread if you prefer) adds creamy richness that ties it all together. Feel free to experiment with pickles, avocado slices, or even a bit of melted cheese if you’re not keeping it vegan.

Side Dishes

Pair these burgers with crispy sweet potato fries, a fresh garden salad, or tangy coleslaw for a well-rounded, satisfying meal. Grilled corn on the cob or oven-roasted vegetables also make delicious companions that keep the flavors light and fresh.

Make Ahead and Storage

Storing Leftovers

Store any leftover grilled portobello mushrooms separately in an airtight container in the refrigerator for up to 3 days. Keep burger buns and fresh toppings separate to maintain their texture and freshness.

Freezing

You can freeze the marinated uncooked mushrooms by wrapping them tightly in plastic wrap or placing in a freezer-safe bag for up to 2 months. However, cooked mushroom burgers don’t freeze as well since the buns and toppings can get soggy.

Reheating

Reheat grilled mushrooms gently on a skillet over medium heat for a few minutes until warmed through, or pop them in a preheated oven at 350°F (175°C) wrapped in foil. Avoid microwaving if you can to preserve their juicy texture. Toast the buns separately for that fresh, crunchy contrast.

Frequently Asked Questions:

Can I make the marinade ahead of time?

Absolutely! The marinade can be mixed and stored in the fridge for up to one week. This makes prepping your Marinated Portobello Mushroom Burgers Recipe even quicker when you're ready to cook.

What if I don’t have a grill or grill pan?

No grill? No problem! You can cook the marinated mushrooms in a cast iron skillet or regular pan on the stovetop over medium-high heat. Just watch for even cooking and a nice sear.

How can I make this recipe vegan?

Simply swap out the mayonnaise for a plant-based alternative, like vegan mayo or even mashed avocado. The mushrooms themselves are already vegetarian and vegan-friendly.

Can I use other types of mushrooms?

Portobello mushrooms work best because of their size and meaty texture, but you can try large field mushrooms or even thick slices of cremini. Just adjust cooking time as needed since smaller mushrooms cook faster.

Final Thoughts

Making the Marinated Portobello Mushroom Burgers Recipe is such a rewarding experience — simple ingredients, straightforward technique, and a result that’s juicy and packed with flavor. Whether you’re a longtime vegetarian or just looking to mix up your burger game, this recipe is a fantastic way to bring smoky, savoriness to your table without the meat. I hope you enjoy every bite as much as I do!