Crispy Pork and Kimchi Potstickers

Name: Crispy Pork and Kimchi Potstickers
Ingredients: 1 teaspoon sesame seeds; 1/3 cup soy sauce; 1/4 cup unseasoned rice vinegar; 2 tablespoons water; 1 garlic clove, minced; 1 scallion, thinly sliced; 1/2 pound ground pork; 1/2 pound kimchi (Korean pickled cabbage), drained and finely chopped; 4 scallions, green parts only, thinly sliced; 1 large egg, beaten; 2 teaspoons cornstarch; 1/2 tablespoon sugar; 1/2 tablespoon soy sauce; 1/2 teaspoon kosher salt; 1/4 teaspoon freshly ground pepper; 36 gyoza wrappers; 2 tablespoons vegetable oil; 1 cup water