You can never have too many burger recipes, and this one is perfect for those wanting a lighter version. And it's also a mouthwatering option for vegetarian guests at your next barbecue. The combination of balsamic, earthy mushroom, grilled red onion, and bubbling gruyère is so decadent and satisfying — you might find your meat-eating friends noshing on these instead!
These burgers are delicious charred over a charcoal grill with a cold beer during the Summer, but also taste fabulous during cooler months when cooked on an indoor grill pan. The caramelized flavors are so rich paired with a brioche bun.
Serve alongside your favorite salad or a handful of chips for a dinner in less than 20 minutes.
- 1/4 cup olive oil
- 1/4 cup balsamic vinegar
- 1/4 teaspoon oregano
- Coarse salt and ground pepper
- 4 slices red onion
- 8 portobello mushrooms (about 1 pound total), stems removed
- 4 brioche hamburger buns
- 4 slices gruyère cheese
- 4 lettuce leaves
- In a bowl, whisk together the oil, vinegar, oregano, and a dash of salt and pepper. Toss the mushrooms several times in the marinade to fully coat. Marinate at room temperature for 30 minutes or up to 2 hours.
- Lightly oil grates, and heat your grill to medium. If using charcoal, you can toss the portobello burgers over nice, hot coals. Or, if using a grill pan, preheat on high for 2 minutes. Grill mushrooms, covered, 3 to 4 minutes per side, or until lightly charred and tender. If using a grill pan, cook for 5 minutes per side, then flip.
- Slice 4 rounds from the red onion and dip in the remaining portobello marinade while holding the rings together. Place each round flat on the grill and cook alongside the portobellos for 3 to 4 minutes on each side.
- Top 4 of the 8 portobellos with a slice of gruyère and cover until cheese is melted. If using a grill pan, cover with tinfoil to help the cheese get gooey.
- Assemble the burgers in this order: bottom bun, lettuce leaf, a slice of grilled red onion, gruyère-topped portobello mushroom (cheese side up), another portobello (cap side up), top bun.
- Other, Main Dishes, Sandwiches
- 4 burgers