01 - Whisk together flour, sugar, yeast, cinnamon, allspice, nutmeg, and salt in a large mixing bowl.
02 - Rub softened butter and orange zest into dry ingredients. Pour in lukewarm milk and add egg. Mix until shaggy dough forms.
03 - Knead by hand or stand mixer for 8-10 minutes until smooth, elastic, and passes windowpane test.
04 - Gently fold currants into dough until evenly distributed throughout.
05 - Place dough in lightly oiled bowl, cover with plastic wrap or towel, and let rise in warm place until doubled, approximately 1 hour.
06 - Turn dough onto lightly floured surface. Divide into 12 equal portions and shape into tight rounds by tucking edges underneath.
07 - Arrange buns on parchment-lined baking sheet with 2 inches between each. Cover and proof 45 minutes until puffy and doubled.
08 - Heat oven to 400°F.
09 - Whisk flour and water to create thick, pipeable paste. Transfer to piping bag or plastic bag with corner snipped.
10 - Pipe straight vertical line followed by horizontal line across each bun to form crosses.
11 - Bake 20-25 minutes until deep golden brown and internal temperature reaches 190°F.
12 - Heat apricot jam with water until thin. Brush immediately over hot buns for glossy finish.
13 - Transfer to wire rack and cool completely. Serve warm or room temperature with butter.