Grilled Portobello Avocado Burgers (Printable Version)

Marinated, charred portobello caps layered with avocado, tomato, lettuce, and tangy mayo for a hearty cookout sandwich.

# The Ingredients You'll Need:

→ Mushrooms & Marinade

01 - 4 large portobello mushroom caps, stems removed and gills scraped
02 - 3 tbsp olive oil
03 - 2 tbsp balsamic vinegar
04 - 2 tsp soy sauce (or tamari for gluten-free)
05 - 2 cloves garlic, minced
06 - 1 tsp dried oregano
07 - ½ tsp smoked paprika
08 - Salt and black pepper, to taste

→ Burger Assembly

09 - 4 burger buns (use gluten-free if needed)
10 - 1 ripe avocado, sliced
11 - 4 slices tomato
12 - 4 leaves lettuce (romaine or iceberg)
13 - ½ red onion, thinly sliced
14 - 4 tbsp mayonnaise or vegan mayo
15 - 2 tsp Dijon mustard

# Step-by-Step Instructions:

01 - In a small bowl, whisk together olive oil, balsamic vinegar, soy sauce, minced garlic, oregano, smoked paprika, salt, and pepper.
02 - Brush the marinade over both sides of the portobello caps. Let them marinate for 10-15 minutes while you prepare the toppings and preheat your grill (or grill pan) to medium-high heat.
03 - Grill the mushrooms, cap side down first, for 4–5 minutes per side, until tender and slightly charred.
04 - Toast burger buns lightly on the grill, if desired.
05 - Spread mayonnaise and Dijon mustard on the bottom half of each bun. Layer with lettuce, grilled portobello, tomato slice, avocado slices, and red onion. Top with remaining bun half.
06 - Serve immediately with your favorite side dishes.

# Additional Tips::

01 -
  • Grilled portobello mushrooms soak up the marinade, transforming into juicy, steak-like patties every single time.
  • Between the creamy avocado and crisp veggies, each bite feels indulgent but manages to be fresh and light too.
02 -
  • I once tried grilling the mushrooms without enough oil, and they stuck like glue – always oil the caps first.
  • Letting the mushrooms sit in the marinade for at least 10 minutes makes all the difference in depth of flavor and juiciness.
03 -
  • A brush with marinade halfway through grilling adds an extra hit of tang and moisture.
  • A sprinkle of flaky salt on the avocado just before assembly wakes up all the flavors.
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