Whisk together the dry ingredients (flour, baking powder, baking soda, cinnamon, salt) in a medium bowl and set aside. In another bowl mix together the oats, chocolate chips, cranberries and pistachio pieces.
In mixing bowl or bowl of a stand mixer beat the butter and shortening for a minute on medium speed then add the sugars and beat until light and fluffy, 7-8 minutes. You want this mixture really light and fluffy.
Add in the eggs one at a time and mix well after each addition then add in the vanilla and milk. Add the dry ingredients and mix on low speed until just mixed. Add in the oats/chocolate chips/cranberries and pistachio mix and stir gently to combine. Chill the dough in a bowl wrapped with plastic wrap/cling film for 2 hours up to overnight.
When ready to bake heat oven to 375 Deg F (190 C)
Scoop 2 rounded tablespoons of dough on cookie sheets prepped with either bake mats or parchment paper. Bake for 10-12 minutes. Cool for a minute on the baking sheet then transfer to a wire cooling rack to cool completely.
This recipe makes around 40 3" cookies. I used