For the biscuits
- Preheat oven to 220°C (200° fan) | 425F | gas 7. Line a large rimmed baking sheet with parchment paper.
- Whisk together flour, sugar, baking powder, baking soda and salt in a large mixing bowl.
- Add butter and rub into flour mixture until it resembles rough breadcrumbs.
- Stir in buttermilk until it's evenly moistened. Scoop out about 1/4 cup portions of the batter and place on the sheet, spaced apart. Brush with beaten egg wash.
- Bake biscuits for about 14-18 minutes until golden-brown and puffed. Remove to cooling rack to cool.