White Chocolate and Cranberry Saffron Braid

Name: White Chocolate and Cranberry Saffron Braid
Cuisine: European, British
Ingredients: 50g (3½ tbsp) butter; ½ gram (¼ tsp) ground saffron; 200ml (⅘ cup) milk; 1 egg; 7g (2¼ tsp) dried yeast (see note 1); 100g (½ cup) sugar; 300-450g (2½ cups - 3¾ cups) spelt flour (see note 2); 65g (2¾ oz) fresh cranberries (see note 3); 1 tbsp sugar; 1 tbsp water; 150g (5¼ oz) white chocolate (cut into chunks); 1 egg (for the egg wash); icing sugar (for sprinkling)