Mix your sultanas, mixed peel, orange zest and orange juice and lemon zest together and set aside to soak for at least 10 minutes (keep stirring intermittently to be sure they are equally soaking up the juice).
Sift together your flour, salt and spices into a large bowl (or your stand mixer bowl).
Stir in your sugar and then your yeast and make a well in the centre, ready to pour your wet ingredients into.
Heat your milk until warm, it should be warm but not hot, similar to the temperature of baby's bath water.
Fit your dough hook to your stand mixer and pour your warm milk into your flour mixture. Mix for about 20 seconds on a low setting to start to incorporate the milk .
Add your 3 eggs and again mix until they just start to combine.
Add your butter (this must be really nice and soft so that it easily breaks down) and then leave to mix on the lowest setting of your mixer for 9 minutes. Stop every 2-3 minutes to give the bowl a wipe-down with your spatula to ensure all of the flour is being incorporated.
The dough is ready once it has an elastic quality to it. It will be quite wet and tacky i.e. wetter than normal bread dough.
Add your soaked sultanas and vanilla extract to the dough and mix for another minute.
Remove the dough from the mixer bowl and place it on a very well floured surface.
Oil the bowl, to stop the dough from sticking when you replace it, I used olive oil.
Knead the dough a few times, then make it into a ball shape and return it to your oiled bowl, cover the bowl with oiled clingfilm (plastic wrap).
Leave to rise in a warm place for 1-2 hours. It is ready when it has doubled in size, so the length of time needed depends on how warm your room is.
Line the base of your baking sheets with greaseproof (parchment) paper.
Tip your brioche dough out onto a floured surface, form it into a large circle, cut it into quarters and then each quarter into 3. Each piece should weigh around 100 grams each. Roll each one into a ball, try to ensure the top is smooth
Place the balls onto your lined baking trays, leave a gap between each one of about an inch.
Loosely cover the trays with oiled clingfilm (plastic wrap) and leave the buns to rise for 30-45 minutes.
Meanwhile, make your paste for your cross.
Mix your flour with your cold water until it form a smooth paste, try not to overmix otherwise it will become rubbery.
Cut the tip off a piping bag (about ½cm wide) and fill with the paste, squish it down to the base.
Heat your oven to 220°C/200°C Fan/425F/Gas mark 7.
Once your brioche buns have risen again, pipe a cross over the top. Start at the bun nearest to you and pipe a continual line, so that it runs over each bun, then repeat with a line the other way. Hold the bag above the bun as you squeeze so that it drops onto it.
Bake for 20-25 minutes until nice and browned.
Whilst making heat your apricot jam until runny, as soon as your buns are out of the oven paint your melted jam over the top using your pastry brush.
Leave to cool on a cooling rack.