Beat shortening at medium speed with an electric mixer until creamy; add peanut butter and sugars, beating well. Add eggs, 1 at a time, beating until blended after each addition.
Whisk together flour and next 4 ingredients in a small bowl. Gradually add to butter mixture, beating well. Stir in 1 cup peanuts and chocolate chunks.
Shape dough into 2-inch balls (about 2 tablespoons dough each). Place on ungreased baking sheets, and flatten slightly.
Bake, in batches, at 375° for 12 to 14 minutes or until lightly browned. Cool on pan 1 to 2 minutes; remove to a wire rack.
Store extra cookies in an airtight container up to one week or freeze up to three weeks.