Combine warm milk with sugar and brewer's yeast, if used. If you use sourdough powder instead, add it in a large bowl together with the flour.
Add to the flour the milk and sugar mixture, salt and melted vegetable spread. Knead until you get a smooth dough, cover the bowl with a clean towel and let rise for 1 hour.
Knead the dough again for 10 minutes, cover it and let rise 1 hour more.
Roll out the dough into a 1/2 inch thick rectangle, brush it with the melted spread for the filling and sprinkle with brown sugar and cinnamon. Roll the rectangle along its short side then cut it into six slices about 1 inch thick to obtain the cinnamon rolls.
Put the rolls on a baking sheet covered with parchment paper, brush with the milk and sprinkle with a little brown sugar and cinnamon. Let rise for 1 hour.
Bake the cinnamon rolls in preheated oven at 320°F for 18 minutes. Serve warm or room temperature.
My vegan cinnamon rolls keep well closed in a food bag up to 5 days. You can also freeze them individually after baking, then put them directly from the freezer into the oven at 400°F for 5 minutes.