To make the batter, combine 1/3 cup flour, salt and peppercorn in a bowl.
Slowly add beer while mixing well. Set aside.
Add 1/2 - inch deep cooking oil in a heavy skillet. Heat oil for deep frying.
Place remaining flour on a plate and dredge catfish on at a time.
Dip fish slices batter, and fry in the preheated skillet with oil, about 4 minutes per side or until golden and crisp.
Drain fish on paper towels. Serve with coleslaw and lemon wedges.