Stir together the soy sauce, sweet chili sauce, mayonnaise, garlic powder, cornstarch, and honey in a bowl. Slice the salmon into thin strips and toss them in the marinade. Let them sit for a few minutes to absorb flavor, then sear in a skillet over medium heat with the marinade until caramelized and cooked through.
While the salmon cooks, prepare the vegetables. Slice the carrot, cucumber, cabbage, and bell pepper into thin strips, and slice the avocado. Pick the mint and cilantro leaves.
Dip each rice paper sheet in water for about 5 seconds, then place it on a clean, dry surface. Lay a lettuce leaf in the center and top with a few strips of salmon, vegetables, and herbs. Fold the sides inward and roll tightly, like a burrito. Work quickly, as the rice paper softens fast.
To make the dipping sauce, whisk together the peanut butter, soy sauce, maple syrup, garlic, ginger, water, sesame oil, and chili flakes until smooth.
Serve the rolls fresh with the peanut sauce on the side.