Preheat the oven to 425°F (220°C), Gas mark 7. Sift the flour into a bowl with the salt and bicarbonate of soda. Stir in the sugar and then, using your fingertips, rub in the butter until the mixture resembles fine breadcrumbs.
Make a well in the center and pour in the buttermilk and beaten egg. Using a tablespoon, gently and quickly stir the liquid into the flour. It should be soft but not sticky. Lightly flour the work surface. Turn the dough out onto it and pat into a circle about 1in (2.5cm) thick. Cut into triangles with a sharp knife or stamp out 2in (5cm) rounds with a cutter.
Arrange the scones on a non-stick baking sheet and bake for 15 minutes until well risen and golden brown. Leave to cool for at least 10 minutes on a wire rack, then serve with the butter curls and jam.
Mix ¼ cup (1oz) (25g) of Kerrygold grated Aged Cheddar in with the buttermilk. Brush the finished scones with melted Kerrygold butter and sprinkle with another ¾ cup (3oz) (75g) grated Kerrygold Aged Cheddar before baking. Mix 1 teaspoon wholegrain mustard into 2 tbsp (1oz) (25g) of butter and use to spread on the split baked scones before topping with sliced cooked ham or tomatoes to serve.
Add ½ cup (2oz) (50g) of sultanas or raisins or dried pitted cherries when stirring the sugar into the dry ingredients, then finish as described above.