Submerge 200 g rice and 150 g urad dal in plenty of water in a large bowl, leaving them to soak for 3 to 4 hours.
Drain the soaked grains and transfer them to a food processor or blender. Grind to a thick, smooth batter while gradually incorporating 500 ml water.
Warm 13.5 g vegetable oil in a small skillet over medium heat. Add the tempering spices and sizzle for about 1 minute until they pop. Stir in 1 g curry leaf and 2 chopped onions, cooking for 2 minutes, then add 40 g fresh coconut and fry for another 2 minutes.
Pour the cooked aromatics into the batter along with 3 g coriander leaf and salt to taste, mixing thoroughly.
Bring vegetable oil for deep-frying to 180°C (350°F) in a deep pan, then ease back the heat slightly. Form the batter into lime-sized balls and drop them in batches into the hot fat. Fry for 1 to 2 minutes, turning continuously until deep golden and crisp, then lift out with a slotted spoon to drain on paper towels.
Use the same weight. The seeds are smaller and hotter; fry in hot oil until they pop, about 20–30 seconds, and reduce the heat if they darken too fast. The dish will be a little sharper.
Use 70% of the weight of whole seed, added with the other ground spices rather than fried whole. You lose the popping texture and the heat comes through more evenly.
Use 80% of the weight, finely shredded and browned slowly with a pinch of asafoetida. Replicates the bulk and natural sweetness in gravies without allium.
Use 50% to 60% of the weight, soaked in equal parts warm water for 15 minutes before grinding. Works well for chutneys, though texture is slightly finer and sweeter.
Use 1.2 times the weight in curries. Adds creamy richness and authentic flavour, but makes gravies smoother and eliminates the grated, chewy mouthfeel.