This dish was inspired by a visit to the central market in Oaxaca. Smoky grilled chicken and vegetables, a quick guacamole, and romaine tossed with a creamy dressing are ready for diners to create their own custom tacos.
Olive oil, ¼cup, plus 1tablespoon
Smoked paprika, 4teaspoons
Ground cumin, 1¼teaspoon
Ground coriander, 1¼teaspoon
Skinless, boneless chicken breast halves, ¾–1lb (375–500g), halved horizontally
Kosher salt and freshly ground pepper
Long, slender zucchini, 2, trimmed and quartered lengthwise
Poblano chiles, 2, quartered lengthwise, seeded
Large red bell pepper, 1, quartered lengthwise and seeded
Red onion, 1 large, halved through the stem end, then cut crosswise into slices ½ inch (12 mm) thick
Gluten-free corn tortillas, 8–12 (5½–6-inches/14–15 cm in diameter), warmed
In a small bowl, mix together ¼cup (2fl oz/60ml) of the oil, the paprika, cumin, and coriander. Place the chicken on a small baking sheet and brush lightly on both sides with the oil mixture. Sprinkle with salt and pepper. Combine the zucchini, poblanos, bell pepper, and onion in a large bowl. Add the remaining oil mixture and toss to coat. Sprinkle with salt and pepper.
Prepare a grill for direct-heat cooking over high heat. Meanwhile, in a bowl, combine the lettuce, remaining 1 tablespoon oil, cilantro, lime juice, and mayonnaise and toss to blend. Season to taste with salt and pepper.
Place the vegetables on the grill rack, cover, and cook until browned and tender, about 6 minutes on each side. Transfer the vegetables to a platter. Add the chicken to the grill, cover, and cook until springy to the touch and cooked through, about 2½ minutes on each side. Cut the vegetables and chicken into thin strips and arrange on a warmed platter. Serve with the romaine, guacamole, and tortillas, allowing diners to fill tortillas with chicken and vegetables, then guacamole and lettuce.