Keep your mince meat out of the refrigerator. In case you are making fresh mince meat, then let it cool down completely before using it in the recipe.
In a mixing bowl, cream together butter and both the sugars.
Add the egg and give it a whisk to incorporate the egg.
Add the flour and then the mincemeat and bring it all together in a dough. This dough is particularly soft and sticky.
Take 3 nos of parchment paper, about the size of A4 sheet.
Divide the dough in 3 equal parts.
Now place each part of the dough on each long end of the parchment paper and spread it out length wise into a roll. Roll the dough in the paper into a cylinder.
Once you have three cylinders, place them in the refrigerator for about 4 - 5 hours or until they are firm.
Once they are firm, take each cylinder one at a time.. In the meanwhile, heat the oven to 170 degrees Celsius.
Unroll the parchment paper and cut the dough in slices (about 7- 8 mm approx thickness).
Arrange each cookie dough on either a silicon mat or more parchment paper on the cookie tray.
Since there is only one egg, it does not spread too much while baking.
Bake each batch at 170 degrees Celsius for 12 to 15 minutes. Watch your cookies like a hawk or else they will burn at the bottom. The minute they turn golden, take them out and place on a wire rack to cool down. If you want really crispy cookies, almost like biscuits, you have to let them turn light brown from golden.