Roll each slice of pickled cucumber in flour, then dip in egg and roll in Panko breadcrumbs, pressing the crumbs tightly for an even coating. Place the prepared slices on a baking sheet covered with baking paper. Bake in a preheated 180 degree oven for 15 minutes, turn over and bake for another 15 minutes, until they are golden and crisp. If the slices are still pale, increase the baking time.