Place the fruit into a bowl, cover with boiling water and set aside.
To make the dough, combine the flour, yeast and sugar in a large mixing bowl and sprinkle over the salt. Over a low heat melt the butter and Dark Chocolate in a small saucepan. Once melted, add the milk and continue to heat until it reaches 37°.
Tip the milk mix into the flour mixture and bring together with fingertips until a sticky dough forms. Tip it out on to a work surface and knead until it comes together. It is quite a wet mixture so this may take about 10 minutes.
Place in an oiled bowl, cover with cling film and leave until doubled in size. Preheat the oven to 200°C (180° Fan, Gas Mark 6).
Tip on to a floured surface and roll out into large rectangle about 5mm thick. Spread with the softened butter.
To make the filling, drain the fruit and combine with the remaining filling ingredients. Sprinkle over the buttered dough.
Starting from a long side, roll in to a fairly tight, long sausage. Divide into 12 pieces. Arrange on a 35cm x 26cm deep sided roasted tin, cut side up. Cover with cling film and leave to prove until only about 1cm of space remains between each bun.
Bake in the centre of the oven for 15-18 minutes. Remove from the oven, whilst hot glaze with the apricot jam. Transfer to a cooling rack and allow to cool completely. Once cooled melt the white chocolate and drizzle using a teaspoon over the top of the Chelsea buns.