½ cup raisins
1 cup hot water
1½ cups plus 2 tbsp. (6½ oz.) white whole wheat flour
½ cup (1½ oz.) old-fashioned oats
2½ tbsp. (1¼ oz.) granulated sugar
2 tsp. baking powder
½ tsp. baking soda
½ tsp. salt
1 tsp. ground cinnamon
Dash ground ginger
8 tbsp. (4 oz.) cold unsalted butter, cut into small pieces
2 tsp. vanilla extract
2/3 cup buttermilk
Sparkling sugar, for topping (optional)
Place the raisins in a bowl and cover with hot water. Let stand for 30 minutes. Drain the raisins and spread into an even layer on a clean kitchen towel. Press gently with another towel to help blot away all the excess water.
To make the dough, combine the flour, oats, sugar, baking powder, baking soda, salt and spices in a medium bowl. Whisk briefly to blend. Add the butter to the bowl and cut the butter into the dry ingredients using a pastry cutter or two knives until the mixture resembles coarse meal and the largest butter pieces are the size of peas. Stir in the vanilla and buttermilk and mix gently with a fork until a dough forms. Fold in the raisins. Turn out onto a lightly floured surface and knead a few times by hand until the dough is cohesive. (Be careful to avoid over handling the dough, as it can result in tough, dense scones.)
Preheat the oven to 400˚ F. Line baking sheets with silicone baking mats or parchment paper. Pat the dough into a 12 x 4-inch log. Cut the rectangle crosswise into 4 equal rectangles. Cut each rectangle diagonally to form 2 triangles. Transfer to the prepared baking sheets. Brush the top of each scone very lightly with additional buttermilk and sprinkle with sparkling sugar if desired.*
Bake, rotating the pans halfway through baking, until the tops are golden brown and the scones are baked through, about 13-15 minutes. Let cool 2-3 minutes on the baking sheet, then carefully transfer to a wire rack to cool further. Serve warm.
*At this point, the shaped, unbaked scones may also be frozen on a baking sheet and then transferred to a freezer-safe container. Bake as directed straight from the freezer, simply adding a few minutes to the baking time and checking for doneness.