Preheat grill pan over medium high. In a medium bowl, whisk the oil, garlic, five-spice powder, ½ tsp salt and ½ tsp pepper.
Add shrimp and toss.
In another small bowl, toss the scallion and sesame seeds.
Cook the shrimp, turning once, until firm and opaque. About five minutes. Sprinkle with the scallion and sesame mixture.
Serves 2