Preheat your oven to 350F.
In a large bowl, mix together the flour, baking powder, baking soda, salt, cinnamon and nutmeg. Set aside.
In a medium bowl, whisk together the sugars, milk, egg, butter and vanilla.
Add the wet ingredients to the dry ingredients.
Pour the batter into 12 muffin cups almost all the way to the top.
Then, to prepare the streusel, mix together the flour, brown sugar and cinnamon.
Then cut the butter into the flour mixture until it resembles wet sand.
Then generously sprinkle the streusel topping over the muffin batter.
Bake at 350F for 15-18 minutes or until a toothpick comes out clean when inserted into the muffin.
Store in an airtight container.