Heat oil in a deep-fryer to 350 degrees F. In a small bowl combine hot pepper sauce and water. In a shallow bowl or pie plate combine flour, salt, cayenne pepper, black pepper, onion powder, paprika, and garlic powder.
Pound each of the chicken breasts with a mallet until they are about 3/8 of an inch thick.
Dip one fillet at a time first into the flour mixture, then into the pepper sauce mixture, and then once again in the flour mixture. Set aside and repeat with remaining chicken breasts.
Add the chicken breasts to the deep-fryer (1 or 2 at a time depending on how big your fryer is) and fry for 8 to 14 minutes until light brown and crispy and fully cooked (the internal temperature has reached 165 degrees F.).
Remove the chicken and drain on a plate lined with paper towels. Repeat with remaining chicken breasts.
Spread about 2 teaspoons of the mayonnaise onto the bottom half of the top of each bun. Place cooked chicken breasts onto the top of the bottom half of the bun.
Top with a piece of lettuce and a tomato slice. Add the top half of the bun onto the sandwich mayonnaise side down.