Place the plant milk and dairy-free spread/baking block in a small pan and heat gently until simmering. Take off the heat and allow to cool slightly to hand temperature.
Mix the flour, sachet of yeast, sugar, salt, and spices in a large mixing bowl. Make a well in the centre and pour in the lukewarm milk/butter mixture. Combine with a spoon until a dough forms. Knead the dough by hand on a floured surface or in a mixer fitted with a dough hook for 5-7 minutes until smooth and elasticated. Shape the dough into a ball and place in well buttered/oiled bowl, cover and leave to rise for an approx. 1 and 1/2 - 2 hours) or until doubled in size.
Now add the chocolate chips and orange zest to the dough and knead these ingredients into the dough until evenly distributed. Divide the dough into 12 equally sized pieces and roll each into a ball. Arrange the buns on a large baking tray that's been lined with parchment paper, leaving about a 2cm gap between each bun. Cover lightly and leave the buns to rise for 45-60 minutes or until joined up doubled in size.
Preheat the oven to 200°C / 180°C Fan / 400°F / Gas Mark 6. To make the crosses for the buns, place the plain flour in a small bowl, adding one tablespoon of water at a time until you have a thick paste that can be piped. Spoon it into a piping bag that's fitted with a small round nozzle and pipe crosses on top of the buns.
Bake the buns for 15-20 minutes - do watch them as they pick up colour very quickly. They're ready to take out of the oven when they've turned a light golden colour on the outside.
Once the buns have come out the oven, while they're still warm, make the orange syrup by combining the orange juice and sugar in a small pan. Heat until all the sugar has dissolved and mixture has started to bubble. Brush the hot syrup over the warm buns.
Allow the buns to cool slightly, then they're ready to eat. They'll keep for up to 3 days. Best eaten on the day of baking, but a blast in the microwave or toasting revives them.