Preheat oven to 350 degrees F.

In a stand mixer, using the paddle attachment, mix the ground oat flour, remaining rolled oats, AP flour, brown sugar, baking powder, baking soda, cinnamon, and salt on low speed until combined.

Add all wet ingredients to a large bowl and whisk to combine.

With the mixer on low, add the wet mixture to the dry and mix for 1 minute. Add pistachios and cranberries and mix just to combine, being careful not to over-mix.

Transfer dough to a well- floured surface and knead by hand until all dry bits come together. Flatten with a rolling pin and shape into a 1/2” thick rectangle. Transfer shaped dough to a parchment lined sheet pan.

Beat 1 egg in a small bowl and brush dough with egg wash until fully coated and glossy. Sprinkle heavily with granulated sugar.

Bake at 350 F for 30 minutes. When done baking, transfer to a cooling rack and cool until nearly completely cooled. Lower oven temperature to 300 F. On a large cutting board, slice biscotti into 1” wide pieces using a serrated knife. Return sliced biscotti to sheet tray and bake for an additional 35-40 minutes until perfectly golden and crunchy.

*Can be stored in an airtight container for up to 3 months.