My husband, who grew up in Mexico, taught me years ago that anything wrapped in tortillas is always a smash hit. I set out this grilled chicken (seasoned with cumin, chili powder, and oregano) and assorted toppings and let guests build their own fajitas.
Kid's Steps: Kids can set toppings in bowls and rub the spices into the chicken (washing hands thoroughly afterward).
Place your toppings (avocado, salsa, sour cream and cilantro leaves) in separate bowls and set them on your table.
Next, make the rub. Combine the cumin, chili powder, oregano, and salt in a shallow bowl. Lightly rub the spices into the chicken with your fingertips until the meat is coated on all sides. Heat your grill to medium. Grill the chicken on both sides, just until cooked through, about 8 minutes. Remove from the heat, slice thinly, and set it on a platter.
While the chicken is cooking, toss the pepper and onion in the olive oil. Set them on the grill, using a vegetable screen, if desired, and cook for 5 to 8 minutes, turning once. Remove from the heat and set on the platter with the chicken.
Place the tortillas on the grill for 5 to 7 seconds on each side, turning with tongs, until hot. Set out the grilled chicken, pepper, and onion with the toppings and tortillas. Let guests assemble and roll their own fajitas. Serves 4 to 6.