Preheat oven to 375° F (190° C) Line a large, rimmed baking tray with parchment paper or a Silpat® baking mat and set aside.
Cream shortening and butter with both granulated and brown sugars in a large mixing bowl. Mix in eggs and vanilla extract until well blended.
Add in flour, baking powder, baking soda, and salt. Mix to combine.
Fold in chocolate chips, chopped chocolate and walnuts until thoroughly combined.
Use a large cookie dough scoop to make 24 balls of dough. Place 6 balls of dough on the prepared baking sheet with 1-2 inches in between each ball. Slightly flatten the dough using a fork or the bottom of a glass.
Place the tray in preheated oven and bake 10-12 minutes or until golden brown and cooked through. Remove from oven and cool slightly before serving. Store in an airtight container.