Preheat oil in a large pot of deep fryer to 375˚ F. Prepare the batter using ice cold water or, better yet, ice cold soda water. The soda water bubble make the tempura batter lighter and fluffier. Keep the batter cold by placing it in an ice filled dish.
Coat the crawfish first in dry batter mix, then in the tempura batter.
Carefully drop it into the hot oil. Gently stir the crawfish after they are in the oil to separate the pieces and prevent clumping. Fry until golden brown, about 3 minutes.
Serve with tempura sauce or spicy aioli.
Spicy Aioli
Mix mayonnaise, lime juice chives, black pepper, salt and cayenne.