In a mixing bowl, combine grated lauki, grated beetroot, dahi, and sooji. Mix thoroughly until well blended. Let the mixture sit and rest for about 15 minutes. This resting time allows the semolina to absorb the moisture and soften slightly.

After resting, stir in salt and fruit salt. Mix gently but quickly to incorporate the fruit salt evenly before it activates completely. Add a splash of water if the batter appears too thick; it should be of pourable but thick consistency.

Heat oil in a heavy-bottomed pan or kadhai over medium flame. Add mustard seeds and allow them to crackle. Toss in chopped green chillies and sauté for a few seconds to infuse the oil.

Pour the prepared batter into the pan, spreading it evenly. Cover with a lid and cook over low heat until the base becomes golden and crisp. This may take several minutes, so be patient to avoid burning.

Once the underside is well-browned and firm, flip the handvo carefully using a flat spatula. Alternatively, you can transfer it to a plate and repeat the tempering in the pan, then place the uncooked side back into the pan for even browning.

Cook the second side until it’s crispy and cooked through. To check for doneness, insert a knife or skewer into the center—if it comes out clean, your handvo is ready.

Remove from heat, let it rest briefly, then slice and serve warm.