Preheat oven to 325°. Bake pumpkin seeds in a single layer in a shallow pan 8 to 10 minutes or until toasted and fragrant, stirring halfway through. Cool 10 minutes.
Meanwhile, beat sugar and butter at medium speed with an electric mixer until creamy. Stir in canned pumpkin. Add eggs, 1 at a time, beating until blended after each addition. Add baking mix and pumpkin pie spice, beating until blended.
Gently fold pumpkin seeds into sugar mixture. Cover and freeze 1 hour or until firm.
Divide dough in half. Shape each portion into a 12- x 3-inch slightly flattened log on a lightly greased baking sheet, using lightly floured hands.
Bake at 325° for 35 minutes or until firm. Transfer to wire racks; cool completely (about 1 hour). Cut each log diagonally into 3/4-inch-thick slices with a serrated knife, using a gentle sawing motion. Place on greased baking sheets.
Bake at 325° for 20 minutes; turn cookies over, and bake 20 more minutes. Transfer to wire racks; cool completely (about 30 minutes). Store in airtight containers up to 4 days.