Heat oil in a pan, add mustard seeds and once they sputter, add sesame seeds, hing, curry leaves, salt, sugar and water. Be careful as the water will splutter. After 10 seconds, switch off the stove and squeeze lemon. Mix with a spoon.
1 tablespoon cooking oil, 1 teaspoon mustard seeds, 1 teaspoon white sesame seeds, ¼ teaspoon asafoetida powder, 2 sprigs curry leaves, 1 tablespoon finely chopped coriander leaves, ¼ teaspoon salt, 1 teaspoon sugar, juice of ½ lemon