In a bowl, mix flour, cornstarch, egg, salt, and cold water until smooth.
Stir in zucchini, carrots, and green onions.
Add oil to a non-stick pan over medium-high heat.
Pour batter into the pan and spread evenly.
Cook 3–4 minutes until golden and crispy.
Flip carefully and cook another 3 minutes until both sides are crispy.
Cut into wedges.
Mix soy sauce, vinegar, sesame oil, chili flakes (optional), and sesame seeds.
Serve alongside.
