Skip to main content

Grilled Portobello Burgers with Piquillo Pepper Aïoli and Watercress

4.9

(19)

Spain's famous piquillo peppers add a sweet-spicy edge to the aioli. Idiazábal, a smoky sheep's-milk cheese from the Basque region, is great with the portobellos. If you can't find Idiazábal, substitute smoked Gouda.

Recipe information

  • Yield

    Makes 6

Ingredients

Aioli:

1/2 cup chopped drained piquillo peppers or roasted red peppers from jar
1 tablespoon Sherry wine vinegar
2 teaspoons finely chopped fresh thyme
1 garlic clove, minced
1/2 cup purchased mayonnaise
Cayenne pepper

Mushrooms:

6 large portobello mushrooms, stemmed, dark gills scraped out
1 sweet onion (such as Vidalia or Walla Walla), cut into 1/3-inch-thick slices
Extra-virgin olive oil
2 teaspoons chopped fresh thyme
1 large garlic clove, minced
8 ounces Idiazábal or smoked Gouda cheese, rind trimmed, thinly sliced
6 sourdough rolls (each about 4 inches in diameter), halved horizontally
1 bunch watercress, stems trimmed

Preparation

  1. For aioli:

    Step 1

    Puree first 4 ingredients in mini processor. Transfer to small bowl. Whisk in mayonnaise; season with salt, black pepper, and cayenne pepper. DO AHEAD: Can be made 3 days ahead. Cover; chill.

  2. For mushrooms:

    Step 2

    Arrange mushroom caps and onion slices on baking sheet; brush both sides with oil, then sprinkle with salt, pepper, and thyme. Turn mushrooms, gill side up, and sprinkle with garlic. Let stand at least 30 minutes and up to 2 hours.

    Step 3

    Prepare barbecue (medium-high heat). Place mushrooms, gill side up, and onion slices on rack. Cook until grill marks appear, about 4 minutes. Turn vegetables over, transferring to cooler part of grill. Cover and cook until mushrooms are very tender and onion slices still retain some texture, about 8 minutes. Turn mushrooms, gill side up; top with cheese. Arrange rolls, cut side down, on grill. Cover; cook until cheese on mushrooms melts and cut sides of rolls are golden, about 1 minute longer.

  3. Step 4

    Arrange roll bottoms on plates; spread with aioli. Top each with mushroom, onion slice, and watercress. Spread cut side of roll tops with aioli; press onto watercress.

Read More
Using two entire lemons—pith, skin, and all—cranks up the citrus flavor in this classic dessert.
Keep this easy frittata recipe on hand for quick breakfasts, impressive brunches, and fridge clean-out meals.
Like Greek lemon potatoes and gochujang chicken stir-fry.
Turn humble onions into this thrifty yet luxe pasta dinner.
This one-pot dinner cooks chicken thighs directly on top of a bed of flavorful cilantro rice studded with black beans for a complete dinner.
This is the type of soup that, at first glance, might seem a little…unexciting. But you’re underestimating the power of mushrooms, which do the heavy lifting.
Filberts, goobers, scaly bark nuts: Explore the world beyond almonds in this guide.
You don’t need melted chocolate to make a good brownie