01 -
Preheat oven to 190°C. Line a baking sheet with parchment paper and set aside.
02 -
Place granulated sugar, all-purpose flour, baking powder, and salt into the bowl of a food processor. Pulse briefly to mix.
03 -
Add cold butter pieces to the food processor and pulse approximately 20–25 times, until mixture resembles coarse crumbs.
04 -
Transfer the mixture to a large mixing bowl. Add cold buttermilk or half and half, and vanilla extract. Mix gently with a large spoon until just combined; the dough will be crumbly. If excessively dry, add additional buttermilk or half and half gradually. Gently fold in chopped rhubarb.
05 -
Turn the dough onto a floured surface. With floured hands, knead briefly until it forms a cohesive mass, avoiding excess dry flour. Pat into a rectangle, 2–3 cm thick. Use a 7.5-cm round cutter or a knife to cut dough into desired shapes.
06 -
Arrange scones at least 5 cm apart on the prepared baking sheet. Bake for approximately 20 minutes, until the tops begin to turn golden. Remove promptly to avoid overbaking.