Preheat your oven to 220C/200C fan/gas 7 and lightly grease two baking trays or line with parchment paper.
In a large mixing bowl, sieve together the self-raising flour and salt.
Add the chilled butter to the dry mixture, and using your fingertips, work the butter into the flour mixture until it resembles breadcrumbs.
In a separate bowl, whisk together the eggs, cream, and sparkling wine until smooth.
Make a well in the centre of the dry mixture, and pour in the wet ingredients. Use a fork to stir everything together until just combined.
On a lightly floured surface, bring the dough together. Be careful not to overwork the dough. It will be a little sticky.
Gently roll out the dough to about 2.5 cm (1 inch) thickness and cut out rounds using a straight edge biscuit cutter or drinking glass and place them onto the prepared baking sheet, leaving a few centimetres between each scone.
Brush the tops of the scones with a little beaten egg.
Bake the scones for 12–15 minutes, or until they are lightly golden brown and cooked through.
Remove the scones from the oven and allow them to cool on the baking sheet for a few minutes before transferring them to a wire rack to cool completely.