Make the dough by mixing atta, salt, vegan butter (if using) in a large bowl. Add warm water and make a soft dough. I had to use about 1½-2cups of water for this amount of atta. Cover with a damp cloth and set aside for at least 30 minutes.
In the meantime, make the filling: heat 2tsp oil in a saute pan; add cumin seeds and once the seeds start to splutter, add onions and cook until lightly browned.
Add ginger+garlic paste and red chili powder, cook for 1 minute.
Next add the grated cauliflower and salt. Sprinkle with some water; cover and cook until completely tender and cooked through.
Finally add the mashed potato, mix well and set aside to cool completely.
Once the filling is cool enough to handle, divide the mixture into 8-10 pieces and roll into balls.
Divide the dough into 8-10 pieces and roll into balls; roll one piece into a 4-5" circle, place the filling in the middle; cover with the dough from all sides and roll into a circle. Use dry flour as needed to roll.
Heat a tawa/ griddle on medium-high flame, place the paratha on the tawa and cook for 2-3 minutes on each side or until cooked thoroughly on both sides. Spread some oil/ ghee if desired.