Preheat the oven to 200C/180C Fan/ Gas 6. Line a 12-holemuffin tin with muffin cases. If you prefer, leave out the paper cases and lightly grease the muffin tin.
Sift together the flour, baking powder & salt in a large bowl and set aside.
In another large bowl, firstly, whisk the eggs and the sugar with an electric mixer then the creme fraiche, milk, melted butter and vanilla extract until well combined
Gently fold and mix in the dry mixture to the wet mixture,fold so that the ingredients are only just combined. Then stir in 100g of the finely chopped crystalised ginger into the muffin batter. Do not over-mix the muffin batter.
Spoon the mixture evenly amongst the prepared muffin tin. Sprinkle over the demerara sugar and the left-over ginger on top.This will create a golden crunchy muffin layer.
Bake for approx. 20 minutes, until the muffins are risen, golden and a skewer comes out clean when inserted into the middle of each muffin.
Allow the muffins to cool for at least 10 minutes.Best served warm from the oven with a spoon of crème fraiche. Muffins will keep in an airtight container for up to three days.