Sichuan Chicken Lettuce Wraps

Name: Sichuan Chicken Lettuce Wraps
Ingredients: 1 pound boneless, skinless chicken breasts, trimmed; 2 tablespoons thinly sliced fresh ginger; 2 cloves garlic, smashed; 2 tablespoons toasted (dark) sesame oil; 2 tablespoons reduced-sodium tamari; 2 tablespoons Chinese black vinegar or balsamic vinegar; 2 teaspoons Chinese chili oil; 2 teaspoons ground Sichuan peppercorns; 2 teaspoons sugar; 12 leaves Boston lettuce; 1 English cucumber, cut into matchsticks; ½ cup carrot and/or radish matchsticks; ½ cup thinly sliced scallions; 2 tablespoons toasted sesame seeds