For the filling, in a small bowl, beat the cream cheese, egg and sugar until smooth; set aside. In a large bowl, combine the flour, pumpkin pie spice, baking soda and salt. Beat the eggs, sugar, pumpkin and oil; stir into dry ingredients just until moistened.
Divide half of the batter among 24 greased or paper-lined muffin cups. Drop filling by teaspoonfuls over batter. Top with remaining batter.
Place a pecan on each muffin if desired.
Bake at 350° for 20-22 minutes or until a toothpick comes out clean. Cool for 5 minutes before removing from pans to wire racks.