Combine warm milk, yeast, and 1 tbsp of the sugar. Let sit for 5-10 mins until foamy.
In a stand mixer with a dough hook, mix flour, spices, salt, and remaining sugar. Add yeast mixture, egg, and softened butter. Knead for 5-7 mins until smooth and elastic.
Knead in raisins and orange zest. Place dough in an oiled bowl, cover, and let rise in a warm place for 1-2 hours, until doubled.
Punch down dough. Divide into 12 equal pieces, shape into smooth balls, and place in a greased 9x13 inch pan. Cover and let rise for 45 mins.
Preheat oven to 375°F (190°C). For the cross, mix flour and water into a paste. Pipe crosses onto the risen buns.
Bake for 18-20 mins until golden brown. Immediately after baking, brush with warmed apricot jam for a shiny glaze. Serve warm.
Notes
For a softer bun, place a pan of hot water on the bottom rack of the oven while baking. The glaze is essential for that classic sticky top.