Warm the milk with the butter in a pan until the butter has melted, then add 100ml water to cool the mixture to room temp. Tip the flour, yeast, sugar, spice and 1 tsp salt into a bowl, making sure the yeast is on the other side of the bowl to the salt. Make a well in the flour mixture and pour the milk and butter in, mixing until it forms big flakes, then bring together with your hands. Tip on a surface and knead until smooth (about 5 mins). Put the dough into a large, lightly oiled bowl, cover with a damp tea towel and leave until doubled in size, so about 1-1 ½ hours.
Line a tray with baking paper. Tip the mixed dried fruits into the dough and knead them in, trying to disperse them evenly throughout the dough. Cut your dough into 6 even-sized balls, take each ball and, using the cup of your hand, and pressing down a little with your palm, roll the ball in a circular motion on the surface to create tension across the top of the bun and a neat round shape. Place onto a tray about 5cm away from each other and press down with your palm to flatten the dough down a little, creating the teacake shape. Cover loosely with an oiled sheet of cling film, for a further 45 mins, or until they have doubled in size.
Meanwhile, heat the oven to 200C/180C fan/gas mark 6. Brush the top of each bun liberally with the egg wash, then bake for 20 mins on the top shelf of the oven, until the buns are golden and well risen. Allow to cool on a wire rack, then slice in half, toast and slather with butter if you like.