- Whisk together ingredients for glaze in a saucepan. Heat over medium-low heat until simmering. Reduce heat to low and simmer for 5 minutes until thickened, whisking regularly. Remove from heat and divide into 2 small bowls: one for basting, one for drizzling. Cool for 10 minutes to further thicken.
- Thinly slice chicken breast in half through the side to make two thin pieces. Use the basting glaze to brush one side of each chicken piece. Heat grill (or a grill pan) over medium heat. Grill glazed side of the chicken for 6 minutes, flip and brush with remaining glaze. Discard any remaining basting glaze. Grill 5-6 minutes longer.
- Brush bread with olive oil and grill for 2-3 minutes over indirect heat. Place 2 bread slices on a plate and top each with lettuce, bacon, mango and chicken breast. Drizzle with glaze from the second bowl if desired. Place remaining bread slices on top. Serve right away.