Banana oat cookies
Five ingredients is all it takes to make these irresistible oaty cookies, studded with chocolate chips
Make the dough by creaming together the butter and sugar until pale and fluffy. Add 1 whole egg, 1 egg yolk and the vanilla, and beat to combine.
Sift over the flour and baking powder, then gradually mix the flour into the dough until combined. Wrap and chill for 30 minutes.
Cut the dough in half and roll out on a lightly floured worksurface or in between two pieces of baking paper until about 5mm thick. Cut out cookies from the dough using cutters of your choice, or use a knife to score into squares. Transfer to a baking sheet lined with baking paper or a silicone baking mat, leaving a little room in between each cookie. Repeat with the remaining dough. Chill for 10 minutes while you heat the oven to 180C/fan 160C/gas 4.
Bake the cookies for 10-12 minutes, swapping the trays around halfway if baking more than one batch, until they look pale, dry and sandy. They will firm up more once they are cool. Cool on the tray for 5 minutes until firm enough to move to a wire rack to cool completely.
Whisk the egg white until white and foamy, then add enough to the icing sugar to make a thick paste. Add a little food colouring to the icing, if you like. Use the icing to decorate the biscuits, and leave them to set completely before serving.