To make the lemon mayonnaise, mix the mayonnaise,
yogurt, lemon rind and juice, parsley and capers in
a bowl. Cover and chill.
Cut the fish fillets into thin strips. Place the
beaten egg in one shallow bowl. Mix together the
breadcrumbs, sesame seeds, paprika and seasoning in
another bowl. Dip in the fish strips, one at a
time, into the beaten egg, then into the breadcrumb
mixture and toss until coated evenly. Lay on a clean
plate.
Heat about 2.5cm/1in of oil in a frying pan until a
cube of bread browns in 30 seconds. Deep-fry the
strips in batches for 2-3 minutes, until lightly
golden.
Remove with a slotted spoon, drain on kitchen paper
and keep warm in the oven while frying the
remainder. Garnish with watercress and serve hot
with lemon wedges and the chilled lemon mayonnaise.