Preheat oven to 200°C, 400°F, gas mark 6. Roll pastry to fit a 30cm x 20cm tray bake tin. Line the base and sides of the tin with the pastry, trimming the edge.
Core, pip and chop the apple into small pieces. Place in a large bowl.
Stir the mincemeat into the apple. Spoon over the pastry, spreading evenly.
Put flour and sugar into a bowl, cube butter and rub in until mix resembles fine crumbs. Sprinkle over mincemeat.
Top with almonds, bake in the oven for about 30–35 minutes until golden. Leave to cool a little before serving.
This recipe has one or more red traffic lights. It's fine to eat occasionally or as a treat.