Heat oil in a non-stick pan. Cut red chillies into 4 pieces and remove seeds.
Add asafoetida, mustard seeds, urad dal, carom seeds, curry leaves and red chillies to the pan and sauté till fragrant.
Add cauliflower and cabbage and mix. Add turmeric powder and salt, mix well, cover and cook for 5-7 minutes.
Crush the dhokla and add to the pan and mix well. Add lemon juice and mix again.