Preheat oven to 375degF. Line a 12-muffin tin with papers or spray with baking spray.
In a large bowl add all wet muffin ingredients (butter, eggs, milk, sugars, puree, milk and vanilla) and thoroughly combine.
In a smaller bowl add dry muffin ingredients (flour, salt, baking soda, baking powder, spices) and thoroughly combine. Then add to the wet ingredients and mix together until smooth (batter will be thick).
In a separate bowl, combine ingredient for the topping. (DO NOT over mix - it should be clumpy not a paste)
Spoon batter evenly into lined muffin tin.
Spoon streusel evenly over top of each muffin and press slightly into the batter.
Place in oven to bake for 30 minutes. (or until a toothpick in the center comes out clean). Remove to cooling rack and let sit for at least one hour before storing in an airtight container.