Grilled chicken gets a boost from fragrant Masaman-curry and tart lime. After the bread and meat get some smoky flavor from the grill, they're topped with peanuts and celery for a delightful crunch, then served with sliced mango and lime.
Brush both sides of chicken with curry. Cover with plastic wrap and let stand 15 minutes. Toss celery with lime juice, oil, and peanuts; season with salt and pepper.
Heat a grill or grill pan over high. Grill bread, cut-side down, until lightly toasted, 1 minute. Season chicken with salt; brush grates with oil and grill until browned on one side, 1 to 2 minutes. Flip and grill until just cooked through, 1 to 2 minutes more. Transfer to a cutting board. Stir together mayonnaise and lime zest; spread evenly over cut sides of bread. Slice chicken and arrange on bottom halves of bread. Toss celery mixture with herbs; sprinkle over both halves of bread. Serve with mango slices and a squeeze of lime.