Grilled Portobello Burgers

Indulge in the savory satisfaction of Grilled Portobello Burgers, a vegetarian delight that elevates the traditional burger experience. These substantial portobello mushroom caps, marinated and grilled to perfection, make a delicious and meaty substitute. Scoring the mushroom tops not only helps retain their moisture on the grill but also facilitates the absorption of a flavorful marinade. The result? Mouthwatering, charred mushrooms complemented by a savory feta, sun-dried tomato, and roasted red pepper filling. These flavorful mushroom burgers are then paired with basil mayo, sweet grilled onions, and a bed of fresh baby arugula—all nestled within toasted kaiser rolls.

SERVES 4

INGREDIENTS:

• 4 portobello mushroom caps (4 to 5 inches in diameter), gills removed
• ½ cup extra-virgin olive oil
• 3 tablespoons red wine vinegar
• 1 garlic clove, minced
• ½ teaspoon salt
• ½ teaspoon pepper
• 4 ounces feta cheese, crumbled (1 cup)
• ½ cup jarred roasted red peppers, patted dry and chopped
• ½ cup oil-packed sun-dried tomatoes, patted dry and chopped
• ½ cup mayonnaise
• ½ cup chopped fresh basil
• 4 (½-inch-thick) slices red onion
• 4 kaiser rolls, split and toasted
• 1 ounce (1 cup) baby arugula

INSTRUCTIONS:

1. Marinate Mushrooms: Using a paring knife, create a ½-inch crosshatch pattern (1/16 inch deep) on the tops of the mushroom caps. In a 1-gallon zipper-lock bag, combine olive oil, red wine vinegar, minced garlic, salt, and pepper. Add the mushrooms, seal the bag, turn to coat, and let sit for at least 30 minutes or up to 1 hour.
2. Prepare Filling: In a bowl, combine crumbled feta cheese, chopped roasted red peppers, and chopped oil-packed sun-dried tomatoes. In a separate bowl, whisk together mayonnaise and chopped fresh basil.
3. For a Charcoal Grill: Open the bottom vent completely. Light a large chimney starter filled with charcoal briquettes (6 quarts). When the top coals are partially covered with ash, pour them evenly over the grill. Set the cooking grate in place, cover, and open the lid vent completely. Heat the grill until hot, about 5 minutes.
4. For a Gas Grill: Turn all burners to high, cover, and heat the grill until hot, about 15 minutes. Then turn all burners to medium-high.
5. Grill Onions and Mushrooms: Clean and oil the cooking grate. Remove the mushrooms from the marinade, reserving excess. Brush the onion slices with the reserved marinade and insert toothpicks horizontally through each slice. Place the onions and mushrooms (gill side up) on the grill. Cook (covered if using gas) until mushrooms release their liquid and are charred on the first side (4 to 6 minutes). Flip the mushrooms and onions and continue to cook (covered if using gas) until mushrooms are charred on the second side (3 to 5 minutes).
6. Assemble Burgers: Transfer the onions to a platter and remove toothpicks. Place the mushrooms on a platter (gill side up) and evenly divide the feta mixture among the caps, pressing it down. Return the mushrooms to the grill (feta side up) and cook, covered, until heated through (about 3 minutes).

TIPS:

• Scoring the Mushrooms: Before grilling, lightly score the smooth, non-gill side of the mushroom caps with a ½-inch crosshatch pattern. This technique expedites moisture release and intensifies the mushroom flavor while preventing soggy buns.
• Marinating and Absorption: Allow the mushroom caps to marinate in a mixture of olive oil, red wine vinegar, garlic, salt, and pepper for at least 30 minutes. The crosshatching aids in the absorption of the marinade, enhancing the final taste and texture.
• Customizing Mushroom Size: Adjust grilling times based on the size of your mushroom caps. Larger mushrooms might need slightly more time, while smaller ones might cook faster.
• Grilling Onions: To prevent the onion rings from falling apart during grilling, insert toothpicks horizontally through each slice. Brush the onions with reserved mushroom marinade before grilling.
• Two Grill Options: Follow either the charcoal or gas grill instructions based on your preference. Both methods ensure a deliciously charred result.

Enjoy the deliciously grilled portobello burgers by stacking them on toasted kaiser rolls with basil mayo, baby arugula, and the sweet grilled onions.