You can substitute shallots in sambar with several options, depending on what you have and your dietary preference:

1. Regular onions

- Most common substitute. - Use finely chopped red or yellow onion. - Rough guide: 1 cup sliced shallots ≈ ¾ cup sliced onions (since onions are stronger).

1. Small Indian sambar onions (pearl onions / madras onions)

- These are actually the closest in taste and texture to shallots. - Use 1:1 by volume.

1. Spring onion (only the white + light green parts)

- Milder than onion. - Good if you want a softer flavor. - Use a bit more than the shallot quantity.

1. If you want no onion/garlic (Jain-friendly version)

- Skip shallots completely. - Increase these for flavor: - More tomato - A bit more hing (asafoetida) - Fresh coriander leaves at the end - Slightly more sambar powder - You can also add finely chopped bottle gourd, pumpkin, or capsicum for extra body in place of shallots.

So, for a Jain sambar, the best is to omit onion/shallots and balance flavor with hing, spices, and vegetables.