Place chicken, ricotta, breadcrumbs, herbs, & seasoning into a large bowl. Using your hands, mix well. Divide into 4 equal portions.
Cut pastry sheets in half lengthways. Place a portion of chicken mix lengthways down one side of each pastry half. Roll up pastry to enclose filling. Place rlls seam side down on chopping board, brush with egg and sprinkle with poppy seeds.
Cut each roll into 6 pieces & arrange on an oven tray lined with baking paper.
Cook for about 35 minutes or until pastry is browned and crisp.