If you are using the mincemeat within a couple of weeks, there is no need to cook it before you cook your pies, just mix the ingredients together and store the mixture in the fridge. To save time you can roughly chop the chestnuts, figs, dates and prunes in your food processor.  The cooked mincemeat will keep almost indefinitely, so feel free to double the recipe or just scale the recipe up to use up the dried fruit from whichever your size your packets come in. 

Makes approximately 1.2kg, enough to fill about 80, 7cm mince pies.