The key to this recipe is the freshness of your squid. If you can get them gutted and cleaned all the better, failing that frozen will work too if you don't like getting your hands dirty.
This recipe is from the recently updated The Complete Asia Cookbook by Charmaine Solomon.
1 kg (2 lb 3 oz) squid
60 ml vinegar
750 ml coconut milk
2 onions, thinly sliced
4 garlic cloves, thinly sliced
2 teaspoons finely grated fresh ginger
1 teaspoon ground turmeric
1 teaspoon chilli powder (optional)
2 tablespoons Ceylon curry powder
½ teaspoon fenugreek seeds
1 cinnamon stick
1 stem lemongrass or 2 strips lemon zest
10 curry leaves
1½ teaspoons ghee or oil
Clean each squid, removing the ink sac and discarding the head. Rinse the tubes under cold running water to remove the skin. Drain well and cut the tubes into rings.
Place in a deep saucepan with all the remaining ingredients except the ghee. Bring to the boil, then reduce the heat to low and simmer for about 1 hour, or until the squid is tender and the sauce has reduced and thickened. Remove from the heat.
Remove the squid from the sauce. In a separate saucepan, heat the ghee over medium–high heat and cook the squid. Add the sauce to the fried squid and simmer for 1–2 minutes to heat through. Serve with rice and sambals.