Toss salmon with hoisin sauce. In a large nonstick skillet, heat oil over medium-high heat. Cook salmon until it begins to flake easily with a fork, 3-5 minutes, turning gently to brown all sides.
Serve salmon and lettuce in tortillas; sprinkle with sesame seeds. If desired, top with salsa.
Notes
Look for thick center pieces of salmon so your cubes will be consistently sized for even cooking.
Hoisin sauce is used as both a sauce and condiment in Chinese and Vietnamese cooking. Its flavor is distinctive in two Chinese classics: char siu and moo shu pork.
The flavor of hoisin sauce varies quite a bit between brands, so feel free to adjust the amount used.
Black sesame seeds have a slightly nuttier flavor than white ones. If you don’t have them, use toasted white sesame seeds instead.