In a small bowl mix all of the ingredients for the remoulade.
Cover and refrigerate until ready to use.
Stir together the cornmeal, flour, baking powder and salt in a medium bowl.
Add the onion.
Stir in the egg and milk.
Drop the batter by heaping teaspoonfuls into 375 degree cooking oil, frying a few at a time.
Fry until golden brown.
Drain on a paper towel and set aside to cool slightly.
Add the oil to a medium skillet and warm over medium-high heat. Cook the crab cakes according to the package directions.
Lay the pretzel buns out and spread some of the remoulade on each one.
Lay one crab cake on each of the bottom buns, then add a slice of lettuce and tomato.
Add the top buns to the sandwiches and serve with a side of the hush puppies.