1. In a large bowl, stir together the flour, sugar, baking powder and salt.

2. Grate in the butter (dip it in the flour occasionally if it gets sticky).

   Lightly rub it into the flour with your fingertips. It doesn't need to be completely combined with the flour, so don't worry if a few larger pieces of butter remain.

3. In a jug, whisk together 60ml of the yogurt, milk or buttermilk plus the egg and vanilla extract.

4. Stir the blueberries and lemon zest into the flour and sugar mixture.

5. Pour the contents of the jug into the bowl and fold everything together. If it seems very stiff, add a little more of the yogurt, milk or buttermilk.

6. Put a piece of baking parchment or greaseproof paper on a board or tray and sprinkle over a little flour.

   Scrape the dough out of the bowl and onto the paper. Using a knife or spatula, spread it out into a circle approximately 15 cm in diameter.

7. Brush with yogurt, milk or buttermilk then sprinkle with a little sugar.

8. Place in the freezer for 30 minutes.

   Preheat the oven to 200C/180C Fan/Gas 6

9. Remove from the freezer and cut the dough into 6 equal triangles. Carefully separate the pieces and place so they're not touching.

10. Transfer the sheet of paper to a baking tray and put in the oven.

    Bake until risen, golden and cooked all the way through & a skewer or cocktail stick comes out clean (18-25 minutes: check after 15 minutes & turn the oven down if they're browning too quickly).

11. Transfer the scones, on their paper, to a cooling rack.

    Wait until they're completely cold before adding the lemon drizzle.

Lemon drizzle

1. Put the sifted icing sugar in a small bowl. Add the lemon juice a teaspoon at a time, stirring, until you get the consistency you like.

   Drizzle over the scones off the end of the spoon and leave to set for a few minutes.