Combine yeast, sugar and warm milk together in the mixing bowl of a stand mixer, stirring to combine. Cover and allow to stand in a warm place for 10 minutes or until mixture starts to froth. Add melted butter and egg, stirring to combine.
Add flours, cocoa, mixed spice, cinnamon and salt to the yeast mixture and using an electric stand mixer with a dough hook, mix until dough comes together. Knead the dough for 5 – 10 minutes or until dough is smooth and elastic.
Place dough in a lightly oiled bowl, cover with a clean damp tea towel or plastic wrap and leave to stand in a warm place for an hour or until doubled in size.
Preheat oven to 200°C (180°C fan-forced) and lightly grease a 23cm square cake tin.
Turn dough onto a clean floured surface, knocking the air out of it, knead for a further 5 minutes or until smooth, working in the sultanas, apricots and chocolate, making sure they are well distributed through the dough.
Divide dough into 16 equal pieces and shape into balls. Using a knife gently score a cross on the top of each ball. Place balls into prepared tin, cover and stand in warm place about 30 minutes or until balls have doubled in size.
For the flour paste, combine flour, sugar, oil and water, stirring until smooth. Place paste in a disposable piping bag or clean zip lock bag and snip the corner, pipe crosses over scored crosses.
Bake balls in preheated oven for 25 minutes or until the tops are golden. Remove from oven and turn buns out onto a wire rack. To double check they are cooked, the base should sound hollow when tapped. Brush tops of buns with hot apricot glaze and allow to cool on wire rack.