Add the vegetable oil to a pan on a medium heat and add the onions. Fry until slightly gold and translucent.
Add the ginger garlic paste and cook for a minute.
Add the paprika, ground coriander, ground cumin and garam masala and cook for 30 seconds. Splash in a bit of stock to stop the spices from burning.
Add the passata, and cook for 3-4 minutes. Stir occasionaly.
Add the stock and cook for 5 minutes. Stir occasionally.
For a thicker, smoother sauce, you can blend the curry but this is optional.
If you have blended, add the sauce back into the plan with 50ml of water. Add the pre cooked chicken tikka. Cook on a low heat for 4 minutes.
Take off the heat and add the single cream and kasuri methi and stir.
Garnish the curry with freshly chopped coriander.