This was an attempt to create a curry base using that was aromatic and slightly sweet. It uses little or no chilli but relies on ginger and black pepper for its heat. It has a good depth of flavour and a lasting "warmth".
This recipe is not knowingly based on anything else so comments welcome!

Tested with chicken and lamb tikka and was excellent.

The quantities below make enough for 6-8 servings.

Vegetable base.
2 large (3 medium) onions, finely chopped
40ml vegetable oil
5 cloves garlic, finely chopped
1 stalk celery, finely chopped
30g root ginger, peeled and finely chopped

Spice mixture.
12 green cardamom pods, remove husks
2-3 black cardamom pods, remove husks
1 star anise
6 cloves

Heat the oil in a large saucepan.
Add the chopped vegetables and fry gently without browning for 3-4 minutes.
Put the lid on. Turn the heat to low and cook for 15 minutes.

Take the spice mixture and roast gently in a dry frying pan.
Grind the spice mixture finely using a pestle and mortar.

Add the ground spices to the vegetables together with:
400g tin chopped tomatoes
1 tsp. ground turmeric
2 tsp. sugar (to taste)
1 tsp. salt
1 tsp. ground cinnamon
1 tsp. ground black pepper
1 tsp. ground cumin
1 tsp. hot chilli powder (optional, to taste)

Add a little water to loosen the mixture and simmer gently for 20 minutes.
Liquidise or use a stick blender, blitz until smooth.
Vary sugar, salt and chilli powder to taste.

(If adding extra chilli powder, simmer for a few minutes more to let the flavour develop before re-tasting)

Enjoy!