INGREDIENTS:

For the curry:
½ cup lentils
½ of onion, sliced
4 cloves of garlic, sliced
¼ tsp turmeric
½ tsp Sri Lankan raw curry powder
½ tsp chili powder
5–6 curry leaves
1.5 cm x 1 cinnamon stick
1 cup coconut milk
½ cup water

To temper the curry:
1 tsp mustard seeds (optional)
½ of onion, sliced
2–3 tablespoons oil
3 cloves of garlic, sliced
4–5 curry leaves
4–5 chilis (break into pieces) or 2 tsp of ground chili pieces
Salt to taste

INSTRUCTIONS:
Making the curry:
Wash the lentils and place them in a medium saucepan.
Add all the remaining ingredients, except the coconut milk. Mix well and keep on medium heat to boil the lentils.
When the lentils are boiled, add the coconut milk and bring it to boil again.
Salt to taste. (If you don’t like to temper the curry, you can serve as is.)

Tempering the curry:
When you can see bubbles on the top surface of the curry, transfer it to another saucepan.
Put the oil into the now-empty saucepan and heat it on low heat. When oil is ready, add the optional mustard seeds and sauté for 3–4 seconds (if you are using the mustard seeds), then add onions, garlic, and curry leaves. Fry the mixture for 5–10 minutes. Then add chili pieces and fry for 2–3 minutes.
Add the curried lentils and salt to taste.

This is usually served with rice and bread. You can also serve this dish with rot or parata.

From: http://www.srilankacooking.com/2009/08/parippu-hodi-parippu-curry-dhal-lentils.html