How to Make It
Combine onion, scallions, chiles, garlic, five-spice powder, allspice, black pepper, thyme, nutmeg, and salt in a food processor; process until mixture forms a coarse paste. With processor running, add soy sauce and oil in a steady stream. Transfer mixture to a large, shallow dish. Add chicken, and turn to coat. Cover and refrigerate overnight.
Bring chicken to room temperature. Preheat grill to medium-high (about 450°F). Place chicken on oiled grill grates, and grill, uncovered, turning occasionally, until well browned and cooked through, 35 to 40 minutes. (Cover grill for a smokier flavor.) Transfer chicken to a platter and serve.