Drain olives. Mix the grated cheese with the egg yolk. Gradually add the flour, baking powder and salt and pepper and mix well.
Whisk the egg white until stiff and add it to the mixture gently. Leave to stand for 1 hour.
Heat the oil in a deep sauce pan. Coat the olives in the mixture and deep fry them in small quantities.
Remove them from the oil, drain well and serve hot.