Heat oven to 220C/fan 200C/gas 7. Combine the mincemeat with the nuts, cranberries, apple and lemon zest.
Unroll the pastry and lay it on a lightly floured work surface. Slice off a strip across one end to leave a 23cm square of pastry. From the strip, cut out 15-30 star shapes (depending on whether you want 1 or 2 stars per slice). Thinly re-roll the pastry trimmings until it is all used up. Lay the pastry square on a baking sheet and scatter over the ground almonds. Carefully spread the mincemeat mixture over so that it comes right to the edge of the pastry (the mincemeat shouldn’t spread when baked). Lay the stars in lines across the mincemeat, slightly overlapping them if necessary to fit, so you
can cut out 15 slices when baked. Brush the stars with egg to glaze, if you like.
Bake for 15 mins or until the pastry is golden. Leave to cool. Meanwhile, mix the icing sugar with 2 tsp lemon juice. Drizzle over the cool pastry and cut into 15 slices.