Preheat oven to (190 C) 375 °F
In a medium sized mixing bowl, sift the flour, baking soda, baking powder and spices together and set aside.
In a large mixing bowl, cream the butter with an electric mixer.
Add the eggs and egg whites, one at a time and mix well.
Add Vanilla extract and sweetener and continue mixing.
Add the pumpkin puree and salt and continue beating until thoroughly mixed.
Add the flour mixture, a scoop at a time and mix on low speed until well combined and there are no lumps.
Divide the batter between 12 lined muffin tins.
Make the Streusel.