Some heart-shaped sprinkle icing bits for decoration
Lightly grease baking trays and preheat oven to 180°C.
Cream butter, sugar, essence and egg yolks until creamy. Sift in flour, corn flour, rice flour and baking powder. Stir in oats and ground almonds.
Turn out dough into a basin and mix well. Roll out dough mixture, a little at a time, in between two plastic sheets to about 1/3cm thickness.
Use a heart-shaped cookie cutter to stamp out the biscuits. Place on prepared tray and brush lightly with beaten egg white. Press some heartshaped sprinkle icing bits over and bake in preheated oven for 12-15 minutes or until golden. Remove and cool on wire racks before storing in airtight containers.