Grilled Thai Chicken Sandwich

Preheat grill to medium-high.
Whisk coconut milk, peanut butter, lime juice, 1 tablespoon chile-garlic sauce and soy sauce in a bowl until well combined.
Working on a lightly floured surface, divide dough into 5 equal pieces. Roll each piece into a 6-inch disk with a rolling pin or press into a disk with your hands. Using 1 1/2 teaspoons oil, brush one side of each disk.
Oil the grill rack (see Tip); place the dough, oiled-side down, on the grill and cook until light brown and puffed, 1 to 2 minutes. Brush the dough with the remaining 1 1/2 teaspoons oil, flip and grill until cooked through, but still a little soft, 1 to 2 minutes more. Wrap in foil to keep warm.
Brush chicken with the remaining 1 tablespoon chile-garlic sauce. Place the chicken, bell pepper and onion on the grill. Grill the chicken, turning once, until an instant-read thermometer inserted into the thickest part registers 165u0b0F, 10 to 14 minutes. Grill the pepper and onion, turning once, until lightly charred and cooked through, 8 to 10 minutes.
Slice the pepper and onion. Toss with 1/2 cup of the reserved dressing in a medium bowl. When the chicken is cool enough to handle, slice or shred into bite-size pieces. Top flatbreads with equal portions of the vegetables and chicken; drizzle with the remaining dressing and sprinkle with cilantro. Fold to eat.