Meanwhile, for sauce, stir together soy sauce, vinegar, honey, ginger, garlic, sesame oil, and crushed red pepper in a small saucepan. Bring to a boil, reduce heat, and simmer, uncovered, until liquid is reduced to 1/2 cup, about 10 minutes. Whisk together cornstarch and 1 tablespoon water in a small bowl. Stir into the sauce and cook, stirring constantly, until thickened, about 1 minute.