What You Need
- 4 portobello mushrooms (4 to 5 inches in diameter), stems and gills removed
- 1/2 cup canola oil
- 1/4 cup red wine vinegar
- 1/2 teaspoon granulated garlic
- Sea salt and pepper
- 5 ounces feta cheese, crumbled (1 1/4 cups)
- 1/2 cup jarred roasted red peppers, patted dry and chopped
- 2 tablespoons oil-packed sun-dried tomatoes, patted dry and chopped
- 1/2 cup mayonnaise
- 1/2 cup chopped fresh parsley
- 4 (1/2-inch-thick) slices red onion
- 4 kaiser rolls, split
- 1 ounce (1 cup) baby arugula
Marinate the Mushrooms
Score a crosshatch pattern on the mushroom caps with a paring knife – 1/2 inch apart, about 1/16 inch deep. Creates pockets for the marinade.
In a gallon zipper bag, mix oil, vinegar, garlic, 1 teaspoon salt, and 1/2 teaspoon pepper.
Add mushrooms, seal, and flip to coat. Marinate at least 30 minutes, up to 1 hour.
Prep Toppings
Mix feta, roasted peppers, and sun-dried tomatoes in a bowl. Set aside.
Stir mayo and parsley together in another bowl.
Stick a toothpick horizontally through each onion slice. Keeps the rings together when flipping.
Fire Up the Grill
Charcoal: Open bottom vent completely. Fill chimney with ~6 quarts briquettes and light. When top coals are ashy, dump evenly across grill. Install grate, cover with lid vent open. Heat ~5 minutes.
Gas: All burners on high, lid closed. Heat ~15 minutes, then reduce to medium-high.
Grill Everything
Clean and oil the grate. Remove mushrooms from marinade – save the liquid.
Brush onion slices with leftover marinade. Place onions and mushrooms (gill side up) on grill.
Cover if using gas. Grill ~4-6 minutes until mushrooms release juices and get char marks.
Flip everything. Grill ~3-5 minutes more for char on the second side.
Stuff and Warm
Move onions to a platter and pull out toothpicks. Set mushrooms gill side up.
Divide feta mixture between mushroom caps, pressing gently so it stays.
Return stuffed mushrooms to grill (feta up), cover, and warm ~3 minutes.
Build the Burgers
Tent mushrooms with foil. Grill rolls cut side down ~1 minute for light char.
Spread parsley mayo on bottom buns. Stack mushroom, then onion, then arugula. Cap with top bun.
Serve immediately while warm.
Pat everything dry before mixing – wet ingredients make the feta mixture watery. The toothpick trick is genius for grilling onions. Kaiser rolls hold up better than regular burger buns here.
Grilled Portobello Burgers
Ingredients
- 4 portobello mushrooms 4 to 5 inches in diameter, stems and gills removed
- 1/2 cup canola oil
- 1/4 cup red wine vinegar
- 1/2 teaspoon granulated garlic
- Sea salt and pepper
- 5 ounces feta cheese crumbled (1 1/4 cups)
- 1/2 cup jarred roasted red peppers patted dry and chopped
- 2 tablespoons oil-packed sun-dried tomatoes patted dry and chopped
- 1/2 cup mayonnaise
- 1/2 cup chopped fresh parsley
- 4 1/2-inch-thick slices red onion
- 4 kaiser rolls split
- 1 ounce 1 cup baby arugula
Instructions
- Score mushroom caps in crosshatch pattern, 1/2 inch apart.
- Mix oil, vinegar, garlic, salt and pepper in zip bag. Add mushrooms and marinate 30-60 minutes.
- Combine feta, roasted peppers and sun-dried tomatoes.
- Mix mayonnaise with parsley.
- Insert toothpicks horizontally through onion slices.
- Heat gas grill on high 15 minutes, reduce to medium-high.
- Clean and oil grate. Remove mushrooms from marinade, reserve liquid.
- Brush onions with marinade. Grill mushrooms (gill side up) and onions 4-6 minutes.
- Flip and grill 3-5 minutes more.
- Remove onions. Fill mushrooms with feta mixture.
- Return stuffed mushrooms to grill, cover 3 minutes.
- Grill rolls cut side down 1 minute.
- Spread parsley mayo on bottom buns.
- Layer mushroom, onion, arugula. Add top bun.
- Serve immediately.
