Take grated fresh coconut, chopped green chillies and cumin seeds in a grinder or blender.
Add water and grind to smooth paste. Set aside.
Making curd mixture
In a saucepan or pot, add the sour curd (yogurt), water and turmeric powder.
Whisk to a smooth consistency.
Add salt (as needed) and ground coconut paste.
Mix until well combined.
Making Moru Curry
Keep the saucepan or pot with the curd mixture on stovetop on a low heat.
Keep on stirring at intervals.
Let mixture become hot. When you steam coming from the mixture, switch off the heat. Do stir at intervals. Do not boil. Cover and set aside.
Heat coconut oil in a small pan. Add mustard seeds and let them crackle.
Add curry leaves, fenugreek seeds and dry red chillies (broken and seeds removed).
Add sliced pearl onions and finely chopped ginger.
Mix and begin to sauté on a low heat.
Sauté until onions turn light golden or golden.
Making moru curry
Pour entire tempering mixture with the oil in the cooked buttermilk.
Cover and let the flavors infuse for a few minutes.
Garnish with chopped coriander leaves (optional) and serve hot or warm with steamed rice.
Sour curd: Add buttermilk, preferably sour.
Veggies:Feel free to make moru curry with cooked vegetables. I like yam, taro root, ash gourd and malabar cucumber. You can add greens like spinach, amaranth or drumstick leaves.
Coconut oil: The authentic recipe calls for coconut oil, but you can try making moru curry with any neutral tasting oil or use ghee (clarified butter).
Coconut: Desiccated coconut (unsweetened) can be used in a pinch. Make sure to soak the desiccated coconut flakes in warm water for 20 minutes before making the paste. Coconut can be skipped too. Simply gently heat through the buttermilk and then add the fried tempering ingredients. Include half a teaspoon each of cumin seeds and chopped green chillies in the tempering.