For the mustard sauce: Place the mustard, shallots, garlic, parsley, and lime juice in a food processor. Push pulse to process, then adjust to “on” position and drizzle in the olive oil in a slow, steady stream until all is used up and mayonnaise is creamy thick. Transfer the mayonnaise to a small bowl, stir in sour cream, seasonings and hot sauce to your liking. Cover and refrigerate until ready to serve.

For the shrimp:  Mix together buttermilk and egg in a mixing bowl. Combine flour, cornmeal, cracker meal, cayenne pepper and salt in a separate mixing bowl by blending with a fork or whisk. Dunk rock shrimp into the buttermilk and then dust them with the flour mixture.

To assemble: Heat the frying oil to 350°F in either a deep fryer or in a deep skillet and a clip-on thermometer. Let breaded shrimp sit for 1 minute before dropping them into the hot oil (a few at a time). Skillet or deep-fry the breaded shrimp for 2 to 3 minutes (depending on their size), or until golden brown. Transfer fried shrimp to a paper-towel-lined plate to drain. Arrange on individual plates for either a first course or a main course and serve with rémoulade sauce.