Chicken-and-Mango Salad

Ingredients

• 1/4 cup olive oil plus more for grill grates, for the chicken
• 1/4 cup white-wine vinegar, for chicken
• 1 tablespoon dijon mustard, for chicken
• 4 skinless, boneless chicken breast halves (about 6 ounces each)
• 1 mango, peeled, pitted, and coarsely chopped, for dressing
• 1/4 cup cilantro leaves, for dressing
• 1/4 cup mint leaves, for dressing
• 1 tablespoon curry powder, preferably, for dressing
• 1 tablespoon white-wine vinegar, for madras
• 1/4 cup olive oil, for madras
• coarse salt and black pepper, for madras
• 1 avocado, peeled, halved, pitted, and cut into 1/2-inch-thick wedges, for salad
• 1 large bunch watercress, tough stems removed (3 cups), for salad
• 1/4 cup thinly sliced red onion, for salad