Sift flour, sugar, baking powder, baking soda, cinnamon, nutmeg and ginger in a large bowl, whisking after each addition. Make a well in the center.
In a separate bowl, combine the pumpkin, sour cream, coconut milk, vegetable oil, vanilla extract, egg and egg white.
Pour the wet ingredients into the dry and stir to combine. Spoon the batter into prepared tins, filling about 3/4 of the tin. Mix the sugar topping and sprinkle on top of muffins.
Bake for 25 minutes or until a toothpick inserted into the center comes out clean.