Ingredients
2 cups unbleached all-purpose flour, plus more for dusting
1/2 cup granulated sugar
2 teaspoons baking powder
1/2 teaspoon kosher salt
1/2 teaspoon ground cinnamon
1/4 teaspoon freshly grated nutmeg
1 tablespoon finely grated lemon zest
1/2 cup (1 stick) cold unsalted butter, cut into pieces, plus more for griddle
1/2 cup dried currants
1/2 cup finely chopped candied citrus peel, such as lemon or citron
1 large egg
2 tablespoons whole milk
Superfine or confectioners' sugar, for sprinkling
Preparation
Line two baking sheets with parchment paper; set aside.
In a large bowl, whisk together flour, granulated sugar, baking powder, salt, cinnamon, nutmeg, and lemon zest. Using a pastry blender or your fingers, cut in butter until mixture is a sandy consistency. Stir in currants, candied citrus peel, egg, and milk until a soft dough forms. Gently knead to combine.
On a lightly floured surface, roll out dough 1/4 inch thick. Using a 2-inch fluted square cutter, cut out squares; transfer to prepared sheets. Reroll scraps once and cut out more squares.
Preheat a cast-iron griddle over medium. Lightly brush with butter. Working in batches, transfer dough squares to griddle and cook, turning once, until golden brown, about 1 1/2 minutes per side. Adjust heat as necessary. Transfer to a serving plate; sprinkle with superfine sugar, as desired. Serve immediately, or store in an airtight container at room temperature 3 to 5 days.