A great way to use up leftover mincemeat after Christmas, or as an alternative to mince pies. I guess you could use other fillings but I've only tried mincemeat. They could be served warm as a dessert with cream or cold as a tea time treat.
If you have one and realise (like I did) that you were just going to sit and eat them all right there and then, you can save yourself by wrapping them individually and putting them in the freezer. Or you could make it in advance of and just freeze it whole, although I haven't done that. Defrost at room temperature. It doesn't take long for a bar, but not sure how long it would take to do a whole tray.