Cream the butter and sugars. Add egg. Add vanilla.
In a separate bowl, combine the oats, flour, salt, baking powder and baking soda.
Then combine the butter mix and the flour mix.
Let the dough rest in the fridge for at least 30 minutes.
After the cookie dough has rested, roll it into generous 1 inch balls, and press your thumb down in the centre making a dent big enough to hold a generous teaspoon of mincemeat.
Add a generous teaspoon of mincemeat.
Bake for 12 minutes.
When the cookies are done baking, let them rest on the cookie sheet for 5 minutes, then move them to a baking rack to cool completely.
Notes
I buy mincemeat for all of my holiday baking. For me, it's just one of those things that you don't need to make from scratch. There are so many fantastic mincemeats out there that are as good, if not better than home made. My favourite is the PC Suet-Free 5 Minced Fruits Mincemeat.