In a small milk pan, gently warm the milk and butter/margarine until the butter/margarine has just melted. Do not let it get too hot or boil.
Meanwhile, sift the bread flour, sugar, salt, cinnamon and spices into a large bowl. Add the yeast and gently stir together until combined. Create a well in the middle and pour in the sunflower oil, before pouring in the milk and butter/margarine mixture too.
Use a wooden spoon to bring the ingredients together and create a slightly sticky dough. Turn the dough out onto a floured surface and knead for 10 minutes until the dough is smooth and elastic.
Place the dough in an oiled bowl and cover with a piece of oil cling film, or a damp tea towel. Allow the dough to rise for at least 1 hour, or until it has doubled in size.
Line a baking tray with some greaseproof paper and set aside.. Knock back the dough (by gently punching the air from the dough and pulling it back on itself) before adding the sultanas and orange zest. Turn the dough back out onto a floured surface and knead again until the sultanas and orange zest are evenly distributed through.
Divide the dough evenly into 12 (see notes for tips) and shape into small balls. Place each bun onto the baking tray, leaving a bit of space between to allow them to rise.
Cover the buns with the greased clingfilm and leave to rise in a draft-free place again for 1 hour.
Pre-heat your oven to 200°c (180°c for fan assisted ovens or Gas Mark 4).
In a cup, mix the flour for your cross with a few tablespoons of water until it becomes a smooth paste consistency. Transfer to a piping bag and cut a small hole in the end. Pipe a line on top of the buns, down each row both vertically and horizontally, to create the crosses.
Bake in your pre-heated oven for 13-15 minutes, until golden brown.
Mix the apricot jam with a dash of boiling water to create your glaze. Brush onto the top of your buns whilst they are still hot.
Once cool enough to touch, transfer to a wire rack to cool completely, or enjoy whilst still warm.
For perfectly even Hot Cross Buns, weigh your total dough and divide the total weight into 12 - then weigh out each bun evenly, before shaping them.