In a vessel water water, turmeric powder and salt. Bring the water to rolling boil.
Mean while cut and clean the cauliflower florets.Add in the boil water. Let it boil for only 2minutes and strain immediately.Now rinse with cold water to stop the cooking process and drain the water.Spread on a clean towel or a wide colander to remove excess moisture.
For Batter
In a bowl combine all purpose flour, corn flour, rice flour, salt, red chili powder and ginger garlic paste. Add water gradually and mix well to get a smooth batter.
The batter shouldn't be runny or very thick.
For Coating and frying
Heat oil in pan on medium to high heat.
Now dip the boiled cauliflower florets in and add in the oil.now reduce the flame to medium low and fry for 3-4 minutes. Keep stirring gently.Do not fry on high flame at this stage.
Now increase the flame slightly and keep frying for another 2-3 minutes.Takeout on a paper towel.
For Manchurian sauce
In a pan or wok heat oil, add green chillies, garlic, ginger, curry leaves and onion.saute for 1-2 minutes.
Now add sauces , vinegar, salt and red chili powder.Add water to adjust the thickness. Cook for 1 minute.
Manchurian sauce is ready.Add the fried cauliflower just before serving. Add coriander leaveson top and serve hot.