In a deep frying pan, add 1-1.5 inches of vegetable oil. Fix a candy thermometer to the edge (in the oil but not touching the bottom of the pan) and set heat to medium. Oil needs to reach 375°F before frying.
Line a plate with paper towels and set the pickles slices on it. This will extract some of excess moisture to help keep the flour dredge on when frying.
Prepare your breading mixture by whisking together flour, pepper, Cajun Seasoning, and cayenne pepper in a shallow dish (I used a pie dish). Set aside.
In a separate shallow dish, whisk together buttermilk and egg.
Once oil has reached 375F, prepare 3-4 pickle slices for frying. Do this in batches or the flour dredge will soak into the egg mixture.
Coat pickle slices in flour mixture, then dredge in buttermilk/egg mixture, then coat with flour mixture again. Gently shaking any excess flour off.
Transfer (I use tongs to place, flip, and remove the slices) pickle slices to the oil and fry 3-4 pickle slices at a time for 60-90 seconds on each side or until golden brown.
Carefully remove pickles from oil and transfer to a paper towel lined plate. Make sure you are checking oil throughout so it stays at 375°F.
Repeat until desired amount of pickles are made. Enjoy!