Preheat the oven to 350°F and lightly grease a baking sheet. Set aside.
In a stand mixer fitted with the paddle attachment, beat the butter on medium to high speed for 30 seconds. Add the brown sugar, baking powder, baking soda, and salt. Beat on medium speed until combined.Add the eggs and vanilla. Mix until incorporated.
In 2 additions add the flour on medium-low speed until just incorportaed.
Add the oats to the mixing bowl and mix on low until just incorporated.
Add the dried fruit and nuts to the mixing bowl and mix on low until the fruit and nuts are spread throughout the cookie dough.
Drop the dough by rounded tablespoons full onto the prepared baking sheet.
Bake for 10-12 minutes or until the edges are lightly browned.
Allow the cookies to stand on the baking sheet for a few minutes then transfer to a wire rack to cool completely.