Separate the florets from the cauliflower and clean them. In a pan, heat about 2 tablespoons of oil and then sauté the florets with some salt until they are half cooked and slightly starts to change color. Transfer the florets to a bowl.
I did this exact same thing in my Air Fryer. Layer the cauliflower and spray / brush some oil. Fry in 400 F for about 10 to 12 minutes. Shake the basket once in a while and remove when the florets are lightly browned
In the same pan, add the remaining oil. Add the mustard seeds, nigella seeds and cinnamon stick and fry for a minute until aromatic.
Now add chopped onions and salt and sauté until the onions are translucent.
Add the ginger and garlic to the onions.
Add the prepared pickling masala to the onions and mix well. Cook the masala in medium heat until the spices are cooked through and the oil starts to separate. This should take a good 10 minutes, so keep stirring the masala to avoid burning them.
Add the tomato puree, turmeric powder, red chili powder and the sugar. Cook the gravy until everything comes together (for about 5-7 minutes).
Add the cauliflower florets and yogurt and mix well. Continue to cook on low-medium heat and check for seasonings. Make sure that the heat is low, otherwise the yogurt will curdle and separate.
Once everything comes together, turn off the flame and garnish the Achari Gobi with cilantro.
Serve the Achari Gobhi hot with rice or roti!