In the bowl of a stand mixer, whisk together the yeast, sugar, and warmed milk. Cover with a clean, damp kitchen towel and let sit for 10 minutes, until the mixture is frothy.
Add 2 cups of flour and mix on low using the dough hook attachment. Add the remaining flour along with the cinnamon, nutmeg, salt, vanilla, dairy free butter, and egg. Mix on medium speed until the dough begins to come together. Add in the chocolate chips and mix gently to incorporate.
Once the dough is smooth and slightly elastic, shape it into a ball using well floured hands. Place it back into the bowl, cover with a damp towel, and let rise for 1 hour, or until doubled in size.
Punch down the dough to release the air. Turn it out onto a floured surface and gently shape back into a ball.
Shape the dough into 12 even pieces and roll each piece into a ball. Place the dough balls in a 9×13-inch tray lined with baking paper, leaving space between each. Cover with a damp towel and let rise for 20 minutes.
Preheat the oven to 180°C (350°F). In a small bowl, mix together the flour and water to make a thick paste for the crosses. Transfer the paste to a zip-lock bag, snip off the corner, and pipe crosses onto the buns.
Bake for 25–30 minutes, or until the buns are golden brown and make a hollow sound when tapped.
While the buns are baking, make the glaze. In a small pot, heat the water and sugar over medium heat until the sugar has dissolved.
Remove the buns from the oven and immediately brush them with the glaze. Let the buns cool slightly before serving.