Preheat oven to 350°F. Spray a 12-count muffin pan with nonstick spray or line with cupcake liners.
Make your streusel topping first. Mix together the streusel ingredients of flour, brown sugar, white sugar, cinnamon, chopped pecans and melted butter in medium sized bowl and aside.
Making your pumpkin batter by combining the muffin ingredients of flour, baking soda, baking powder and spices in a large bowl. Set aside.
In a medium sized bowl whisk together sugars, eggs, vanilla, vegetable oil and pumpkin puree until combined.
Pour the wet ingredients into the dry ingredients and gently fold together until they are combined.
Spoon or pour your pumpkin batter into your prepared muffin pan, filling your muffin tins 2/3 of the way full. Add approximately 1 tablespoon of your streusel topping to your muffins keeping in mind your muffins will rise during cooking.
Move your muffin tins to your preheated oven and bake for 19-21 minutes.
After removing your muffins from the oven, allow them to stay in the muffin tin for 5 to 10 minutes before moving them to a wire rack to cool completely.
These pumpkin streusel muffins can be stored in an airtight container at room temperature for 4 to 5 days or moved to the refrigerator for up to a week.