1 (1-pound) pork tenderloin, trimmed
1 teaspoon canola oil
Cooking spray
3 tablespoons fresh lime juice
1 1/2 tablespoons fish sauce
1 1/2 tablespoons lower-sodium soy sauce
1 1/2 teaspoons sugar
1 1/2 teaspoons grated peeled fresh ginger
1/8 teaspoon ground red pepper
1 serrano chile, thinly sliced
3/4 cup small fresh mint leaves
1/2 cup thinly sliced red onion
3 thinly diagonally sliced green onions
1 halved, seeded, and thinly sliced cucumber
8 cups sliced romaine lettuce
1/2 cup cilantro leaves