Heat the oven to 220 degrees Celsius. Lightly grease baking a baking sheet.
Sift the flour, baking powder and nutmeg into a bowl. Add the lemon zest. Mix in cold butter and rub it in until the mixture resembles fine breadcrumbs.
Stir in sugar. Beat the eggs together and 300ml (10fl oz) sour cream. Put about 2 tbsp aside in a cup for later.
Add the egg mixture to the dry ingredients stirring it in until you have a soft dough.
Scatter some flour onto the work surface and turn dough onto it. Sprinkle the dough with a little bit of flour and then gently knead the dough until it is a little smoother.
Flatten it to a thickness of 3cm-4 cm. Use a 21/2 inch cutter (smooth edged cutters tend to cut more cleanly giving a better rise) plunge into the dough, straight down then lift it out straight out. Repeat process. Gently push dough together, knead, flatten and cut out more scone.
Arrange on the prepared baking sheets and brush the tops with the reserved beaten egg mixture
Bake for 10 - 15 minutes until well risen and golden on top.
Transfer to wire rack and leave to cool.