Unroll the pastry and sprinkle most of the cheese over one half of the sheet. Fold the pastry in half to cover the cheese and seal it in.
Dust your rolling pin and work surface with a little flour and put your pastry sheet on it. Roll it out until doubled in size.
Heat oven to 200C/180C fan/gas 6 and line two baking sheets with baking parchment.
Using cookie cutters, cut the pastry into shapes and put them on the prepared baking sheets. (Put the cutters on the dough close together so that less pastry is wasted. You can fold the trimmings back on themselves and re-roll to cut out more shapes.)
Brush the shapes with milk and add a pinch of cheese and a sprinkling of your chosen topping, if using.
Bake in the oven for 10-12 mins or until risen and golden, then transfer to a serving plate. Will keep in an airtight container for 3 days.