ONION TOMATO PASTE PREPARATION: Take a deep pan and heat oil and add onions and saute well, now add tomatoes, cover and cook for 15 minutes or until it turns soft and mash them.
Keep aside to cool down completely. When it is cooled transfer to the blender & blend to smooth paste without adding any water & keep aside.

CASHEW PASTE PREPARATION:
Take a bowl and soak cashews, poppy seeds and almonds in hot water for 15-20 minutes, blend to smooth paste & keep aside.

BASE PREPARATION:
In a same pan heat the oil and add cashew paste and saute for 4-5 minutes at low flame till it cashew paste separates from the wall of a pan.

Now add in prepared onion tomato masala paste and mix well.
When it starts boiling add turmeric, kashmiri red chilli powder, cumin powder, black pepper, jaggery and garam masala, saute on low flame until the spices turn aromatic and mix well in the gravy.

Cook for 10 minutes or until oil separates, stir in between to prevent from burning. Bring the thickness to the desired consistency.

Now curry base is ready. Add some cream & coriander, serve hot with your favourite vegetables or rice or chapati.

Note: You can cool it completely and refrigerate in an airtight box for upto 8-10 days. It can also be freezed for upto a month.

Note : If you want to preserve the base curry you may need to add more cooking oil while preparing the base curry.
Oil helps to preserve the curry for long time.