Place yeast, sugar and milk in a small bowl, whisk until yeast dissolves. Cover with plastic wrap, stand in a warm place (see Notes) for 10 minutes or until mixture is frothy. Sift flour, cinnamon and all spice into a large bowl and rub in butter. Stir in yeast mixture, currants, sultanas, egg and water. Bring together with your hands or a spoon, then turn out onto a floured surface. Knead until smooth, then place in a greased bowl and cover with plastic wrap. Stand in a warm place (see Notes) for 1 hour or until mixture has doubled in size.

Grease a deep 23cm square tin with butter. Remove the plastic wrap from the bowl, then punch the dough to knock it back. Turn dough onto a floured surface and knead for a minute. Divide dough into 16 pieces, form into balls and place in the tin. Cover, and stand again in a warm place (see Notes) for 20 minutes or until dough has doubled in size.

Preheat oven to 180°C. To prepare flour paste, combine flour and sugar in a bowl; gradually blend in enough water to form a thickish smooth paste. Spoon paste into a piping bag with a small plain tube or use a resealable plastic bag and cut off a tiny corner. Pipe crosses onto buns—four long lines vertically and then horizontally across each row of buns.

Bake for 10 minutes then reduce heat to 160°C for about 20 minutes. Turn onto a wire rack and brush with warm orange spread (or not if you don’t like sticky buns).