Put all dough ingredients into a bowl and work with your hands until a shaggy dough starts to come together.
Remove dough from bowl and place on a lightly floured surface & continue to work until a dough ball forms, then wrap in plastic wrap & chill in fridge for 30 minutes.
Preheat your oven to 375ºF and spray (or oil) mini cupcake tins, and set aside.
Once dough has chilled, remove from fridge & place on a floured surface. Then roll with a rolling pin until until thin, about 1/8 inch.
With a small round cookie cutter,or top of a small glass, cut out circles & place each circle into your mini cupcake tin. It should come up & over the the sides just a small amount, similar to a normal pie dough in a pie tin.
Poke holes in the bottom of your mini pie dough with a fork, then par-bake in the oven for 6 minutes. Remove and let cool.
In a stand mixer, start your filling by beating your egg, then add brown sugar, vanilla, & salt and mix well.
Once mixed, add in your pecans (or walnuts) on your slowest speed (or fold in with a spatula by hand) until just combined.
Place a small spoonful of the filling into each mini-pie crust. Careful not to overfill! Then bake in the oven for 18 minutes or until filling becomes more solidified.
Remove from oven and let cool for 10 minutes before removing the pies from the tins. Enjoy!
