Preheat oven to 400°.
In a large mixing bowl, cream butter or margarine, eggs, vanilla, and granulated sugar.
1/2 cup butter or margarine, 1 cup granulated sugar, 1 egg, 1 ½ Tbsp vanilla
Add flour, baking soda, and pumpkin pie spice and mix until well combined.
2 cups all-purpose flour, 1 tsp baking soda, 1/2 Tbsp pumpkin pie spice
Add the pumpkin puree and applesauce and mix until you have a thick batter.
1/2 cup pumpkin puree, 1/2 cup applesauce
Either grease or fill a muffin tin with liners.
Fill each liner 1/3 full of batter. Top with streusel.
Bake for 12-15 minutes.
Allow muffins to cool, then remove from pan and serve!