Preheat your oven to 375°F (190°C) or prepare a grill. Season chicken with salt and pepper, then cook until internal temperature reaches 165°F (75°C), roughly 25-30 minutes. Once cooked, let cool, then shred or dice.

In a large mixing bowl, combine shredded chicken with sweet chili sauce. Stir until well-coated and let sit for a few minutes to absorb flavors.

Wash and prep your veggies. Shred lettuce, slice cucumber, grate carrots, and thinly slice red onion if using. Keep avocado reserved for last.

Take a tortilla and spread a layer of mayonnaise or Greek yogurt. Layer greens, chicken mixture, prepared veggies, shredded cheese, and cilantro. Squeeze lime juice over and season with salt and pepper.

Fold the sides of the tortilla inward and roll tightly from the bottom to enclose the filling. Slice in half if preferred for easier handling.