First things first, preheat your oven to 425°F (220°C). Grab a large baking sheet and line it with parchment paper or a silicone baking mat.
Now, let's sift together 250g of plain flour, 20g of baking powder, and 6g of salt into a large mixing bowl.
Add in 50g of very cold butter cubed and use a pastry cutter to incorporate it into the flour mixture until it forms small crumbs.
In a separate bowl, whisk together 25g of sugar, 125 ml of very cold milk, and 1 large egg. Pour this mixture into the dry ingredients and gently mix until a soft dough forms. Be careful not to over-mix!
Next, press or roll out the dough onto a lightly floured cutting board until it's about 2cm thick. Use a round cookie cutter to cut out 8 scones and place them on the baking sheet. Don't twist the cutter though, or the scones won't rise properly.
For extra fluffiness, pop the scones in the freezer for 20-30 minutes (not longer though!). This will help them rise even more when baked.
Before popping them into the oven, brush the tops of the scones with milk. Bake for 12-15 minutes, or until they're golden brown and smell heavenly.