The Kitchn: You must make these grilled portobello burgers

Kelli Foster, TheKitchn.com on May 9, 2022

1. Heat a grill pan over medium-high heat for 5 minutes. Brush the pan with vegetable oil. Place the onions in the pan in a single layer and cook until grill marks form on the bottom, 2 to 3 minutes. Flip the onions and cook until tender, about 2 minutes more. Transfer to a plate or baking sheet. Meanwhile, remove the mushrooms from the marinade.

2. Brush the pan again with vegetable oil. Working in batches if needed, place 2 of the mushrooms in the pan in a single layer, stem-side up. Cook until marks form on the bottom, about 4 minutes. Flip and cook until tender, about 4 minutes more. Transfer to a plate or baking sheet and tent with aluminum foil to keep warm. Brush the pan with more oil before cooking the remaining mushrooms.

3. If desired, split 4 hamburger buns and grill until toasted and lightly browned, 30 seconds to 1 minute per side.

Option 2: Outdoor grill

1. Prepare an outdoor grill for medium-high, direct heat. Scrape the grill grates clean if needed. Oil the grill grates with a paper towel dipped in vegetable oil.

2. Place the onions on the grill in a single layer. Cover and grill until grill marks form on the bottom, 2 to 3 minutes. Flip the onions and grill until tender, about 2 minutes more. Transfer to a plate or baking sheet. Meanwhile, remove the mushrooms from the marinade.

3. Place the mushrooms on the grill in a single layer stem-side up. Cover and grill until grill marks form on the bottom, about 4 minutes. Flip the mushrooms, cover, and grill until the mushrooms are tender, 3 to 4 minutes more.

If desired, split 4 hamburger buns and grill until toasted and lightly browned, about 30 seconds per side.

Finish

1. Spread 1/2 cup pesto evenly on the cut sides of the buns (about 1 tablespoon per bun half).

2. Place a grilled mushroom, stem-side up, on each bottom bun. Top the mushrooms with the grilled onion, roasted red pepper, 1 packed cup baby arugula, and close with the top bun.

(Kelli Foster is a senior contributing food editor for TheKitchn.com, a nationally known blog for people who love food and home cooking. Submit any comments or questions to editorial@thekitchn.com.)