Place shrimp on paper towels and refrigerate. They must be free of moisture to hold the batter.
Mix together ingredients for the Mustard Sauce and set aside.
Mix together ingredients for the Hot Chile Garlic Sauce and set aside.
For the batter: In a large stainless or glass mixing bowl, mix the cornstarch and flour together. Add the soda water gradually, until a forms smooth thick batter the consistency of pancake batter. Add seeds and herbs. Keep the batter cold and use immediately.
Grab the shrimp 3 or 4 at a time by the tail and dip into the batter. Shake off excess and place in the hot oil. While the shrimp are frying, lay out the plates and drizzle the 2 sauces around using a coffee spoon. Remove the shrimp from the hot oil and place on absorbent paper. Season with sea salt.
Stack the shrimp, 5 on a plate and garnish with the scallions and fried cilantro leaves. Serve immediately and enjoy!
Note: Always get more shrimp as you can easily eat more that 5 of these!