Chicken Sandwiches with Caramelized Onions, Watercress and Paprika Aioli

I think the reason this sandwich is so delicious lies with the not-so-secret sauce. The paprika aioli is so nice and smoky. That, mixed with the sweetness from the caramelized onions, really takes a plain old chicken sandwich to new heights. I couldn't find hot smoked Spanish paprika, so I used smoked paprika plus a pinch of cayenne (in your face specialty store).

CHICKEN SANDWICHES WITH CARAMELIZED ONIONS,
WATERCRESS, AND PAPRIKA AIOLI

Makes 6

1/2 cup mayonnaise

1 tablespoon fresh lime juice

1 teaspoon hot smoked Spanish paprika*

1 garlic clove, pressed

2 tablespoons extra virgin olive oil, plus more for brushing on rolls

2 tablespoons canola or vegetable oil

2 pounds onions, halved lengthwise, thinly sliced crosswise (about 7 cups)

3 (8-oz.) skinless boneless chicken breast halves, cut crosswise in half

6 sourdough sandwich rolls (or 12 ½-inch-thick slices sourdough bread)

3 cups (lightly packed) watercress or arugula

*Sometimes labeled Pimentín Picante or Pimentón de La Vera Picante (available at
  specialty foods stores)

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1.      Whisk mayonnaise, lime juice, paprika and garlic in a small bowl. Gradually whisk in 2 tablespoons olive oil. Season with salt and pepper. Aioli can be made 2 days ahead; cover and chill.

2.      Heat vegetable oil in heavy large skillet over medium-high heat. Add onions, sprinkle with salt, and cook until beginning to brown, stirring often, about 10 minutes. Reduce heat to medium and continue to cook until onions are soft and deep golden brown, stirring often, about 20 minutes longer. Season with salt and pepper. Caramelized onions can be made 2 hours ahead. Let stand at room temperature.

3.      Prepare barbecue (medium-high heat). Place chicken breasts between 2 sheets of plastic wrap. Pound with mallet to 1/3-inch thickness. Sprinkle with salt and pepper. Grill chicken until cooked through, about 3 minutes per side. Transfer to work surface.

4.   Brush cut side of rolls with extra virgin olive oil. Grill rolls, cut side down, until grill marks appear, about 1 minute. Spread rolls with some of aioli. Assemble sandwiches, dividing chicken, caramelized onions, and watercress among rolls. Serve warm.

barely adapted from Americano (San Francisco, CA)

onions before

onions caramelized

aioli ingredients

paprika aioli

chicken on the barbecue

grilled chicken

grilled bread with paprika aioli

caramelized onions on top of aioli

watercress added (the chicken is under there already,
I just forgot to take a photo before I added the watercress)

ready

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