In a pan over medium heat, toast the cumin seeds for 2 to 3 minutes, until slightly brown and fragrant.
In a food processor, add the toasted cumin seeds, mint, cilantro. Thai peppers, amchoor, and salt. Process the mix until chopped very fine (or your desired level of coarseness).
Transfer the mix to a bowl, then add the lemon juice and stir until fully combined.
Use immediately, or for the most robust flavor, allow the chutney to refrigerate for 1 to 2 hours prior to use to allow the flavors to set.