Select the saute mode on the instant pot and heat the oil. Now add the cumin seeds and fry for 30 seconds. Add the onion and cook for 5-7 minutes until the onion turns soft. You can splash with little water while cooking, to avoid burning. Make sure the onions are soft before moving to the next step. Add ginger garlic paste and saute for 45 seconds.
Add the pureed tomato and cook till all the moisture is absorbed and tomato gets thick and the oil starts to ooze out.
Add the turmeric powder, coriander powder, cumin powder, red chili powder, garam masala, tomato paste and salt. Coat the spices with the tomato mixture. If the pot gets too hot and the bottom is burning, cancel the saute mode or splash with some water.
Add the coconut milk and mix it well.
Add the cauliflower florets and mix them with all the spices. Add the paneer cubes and gently stir. Add a cup of water and gently deglaze the pan.
Press cancel, secure the lid and adjust the vent to sealing position. cook on high for 2 minutes.
After 2 minutes, do a quick release by moving the knob from sealing to vent. The curry will look little watery, but will thicken up in few minutes. You can also sauté for 2-3 minutes till the curry thickens slightly. Taste and adjust the seasoning. Finally add lemon juice and fresh coriander leaves.
Let the curry rest for atleast 15 minutes before serving.