Both in and on these traditional scones, use the richest butter you can find—for instance, Ireland's Kerrygold, available in some U.S. supermarkets.
- 6 1⁄4 cups flour
- 1⁄2 cup sugar
- 2 tsp. baking powder
- 16 tbsp. (2 sticks) unsalted butter, cut into pieces
- 3⁄4 cup sultanas (golden raisins)
- 1 3⁄4 cups milk
- 1 egg
Preheat oven to 400°. Line two baking sheets with parchment paper and set aside. Whisk flour, sugar, and baking powder together in a large mixing bowl. Using a pastry cutter or two table knives, cut butter into flour mixture until it resembles coarse meal flecked with pea-size pieces of butter. Stir in sultanas. Add milk and stir until dough just comes together.
Turn dough out onto a lightly floured surface. Dust hands with flour and gently knead with the heels of your hands several times until dough forms a rough ball. (Do not overknead dough, or scones will be tough.)
Divide dough into 20 equal pieces, gently shape each into rounds, and arrange on prepared baking sheets 1"–2" apart. Beat egg and 1 tsp. water together in a small bowl. Using a pastry brush, brush tops of dough rounds with egg wash.
Bake scones until golden brown, 30–35 minutes. Set aside to cool on wire racks for 5–10 minutes. Serve warm with butter and marmalade or jam.