Combine yams, pineapple, 1 cup sugar, lemon and orange rind in a large saucepan. Cook over medium heat, stirring constantly, until thickened. Cool; set aside.
Combine flour, remaining 3 tablespoons sugar, baking powder, and salt; cut in shortening with pastry blender until mixture resembles coarse meal. Sprinkle cold water evenly over surface; stir with a fork until all ingredients are moistened. Divide pastry into 22 to 24 portions. Roll each portion to a 3-inch circle on a lightly floured surface.
Place about 1 tablespoon pineapple mixture on each pastry circle. Moisten edges of circle; fold pastry in half, making sure edges are even.
Using a fork dipped in flour, press edges of pastry together to seal. Sprinkle 1/2 teaspoon sugar on each pastry. Place on baking sheets; bake at 350° for 30-minutes or until lightly browned.