Preheat oven to 375°. Combine 1 1/2 cups sugar, 1/4 tsp. cinnamon, and 1/4 tsp. nutmeg in a saucepan. Stir in 1 1/2 cups water; bring to a boil. Reduce heat; simmer, stirring occasionally, 5 minutes. Remove from heat; stir in 2 Tbsp. butter. Combine flour, baking powder, and salt. Cut in shortening with a pastry blender until crumbly. Cover and chill. Meanwhile, peel and core apples.
Stir milk into flour mixture until moistened. Turn out onto a lightly floured surface, and knead 3 to 4 times. Roll into an 18- x 12-inch rectangle. Cut into 6 (6-inch) squares. Place 1 apple in center of each square.
Combine 1/3 cup sugar and remaining 1/4 tsp. cinnamon and 1/4 tsp. nutmeg; sprinkle over apples. Press 1 piece of butter into each apple center. Moisten edges of dough with water; fold dough over apples, pinching edges to seal. Place dumplings in a lightly greased 13- x 9-inch baking dish. Pour sugar syrup over dumplings.
Bake at 375° for 40 minutes or until golden brown. Sprinkle with pecans.