Wash and soak the rice in water for 4–5 hours, then drain before grinding.
Chop okra into small pieces. Blend it with green chilies, cumin seeds, and grated coconut (if using).
Grind the soaked rice and okra mixture together with a little water to create a smooth, pourable batter.
Stir salt into the batter and let it rest for 15–20 minutes to enhance the flavors.
Preheat a dosa tawa (griddle) and lightly grease it with oil.
Pour a ladle of batter onto the tawa and spread it evenly in a circular motion to make a thin dosa.
Cook the dosa on medium heat until golden and crispy. Flip if needed, and serve with chutney or sambar.