Heat a dry pan over medium-low heat, add semolina, and dry roast, stirring continuously until fragrant and slightly golden for 5-7 minutes. Transfer the toasted rava to a plate and set aside, being careful not to burn it.

In the same pan, heat oil or ghee over medium heat, then add mustard seeds, and once they splutter, add cumin seeds, chana dal, and urad dal, sautéing for 30 seconds until the dals turn light golden.

Add asafoetida, curry leaves, green chilies, chopped onion, and grated ginger, then sauté until the onion turns translucent for 3-5 minutes.

Add the finely chopped mixed vegetables, turmeric powder, and salt, then cook, stirring occasionally, until the vegetables are tender-crisp for about 5-7 minutes.

Stir in the coriander powder and sauté for another minute to allow the aroma to bloom.

Pour in the hot water and bring it to a rolling boil, then check for salt and adjust if needed.

Gradually add the toasted semolina to the boiling water, stirring continuously with one hand to prevent lumps, then reduce the heat to low.

Cover the pan and cook for 5-7 minutes, or until all water is absorbed and the rava is cooked and fluffy; then turn off the heat and let it rest, covered, for another 5 minutes.

Gently fluff the upma with a fork, then stir in the fresh lemon juice and garnish with chopped fresh coriander leaves.