Make the sauce: Mix mayonnaise, chili garlic sauce, sugar, and rice vinegar in a bowl. Refrigerate.
Prepare for frying: a) Combine beaten egg and milk in one bowl. b) Mix flour, panko, and seasonings in another bowl.
Bread the shrimp: a) Coat each shrimp in flour mixture. b) Dip in egg mixture. c) Coat again in flour mixture. d) Arrange on a plate and refrigerate for 20 minutes.
Fry the shrimp: a) Heat oil to 350F in a dutch oven. b) Fry shrimp for 2-3 minutes until golden. c) Drain on wire rack or paper towels.
Serve: a) Coat fried shrimp with ¼ cup sauce. b) Serve with remaining sauce on the side.