Preheat deep fryer to 350 degrees.
In a large bowl, whisk 2 cups of the buttermilk with the hot sauce and soy sauce. Add the chicken livers and turn to coat. Cover and refrigerate overnight.
Remove the livers from the buttermilk, then dredge them in the flour mixture. Set aside to allow coating to adhere to the protein.
Drop half the coated livers into the oil and allow to cook for minutes.
Remove from oil and allow to cool for a bit.
Remoulade: Combine the mayo, mustard, garlic, horseradish, Worcestershire sauce, lemon juice, Cajun seasoning, smoked paprika, cayenne pepper, and parsley in a small bowl. Refrigerate until needed (I like to let the flavors sit for a while, but you can serve it immediately).