In a bowl, combine the first six ingredients. In another bowl, beat the egg; add milk, pumpkin and oil. Stir into dry ingredients just until moistened. Fill 12 greased or paper-lined muffin cups half full.
Place a cream cheese cube in the center of each. Top with remaining batter.
For streusel, combine brown sugar, pecans and cinnamon in a small bowl.
Cut in butter until crumbly.
Sprinkle over batter.
Bake at 400° for 18-22 minutes or until a toothpick inserted in the muffin comes out clean. Cool for 5 minutes before removing from pan to wire rack.