I a skillet over medium heat, dry toast the chiles for 3 minutes. Add the coriander, caraway and cumin seeds and toast another 2 minutes. Let cool.
To a spice grinder (or coffee bean grinder, food processor) add the toasted chiles and seeds, lemon peel, garlic powder and salt. Blitz until ground, doing this in batches if necessary.
Store in airtight container, this makes a little over 3/4 cup total.
Notes
Dried Red jalapeno, Fresno or Thai Birds Eye chile.
I typically use Penzy's Dried Lemon Peel, but if you want you can zest 2 whole lemons, place the zest on a parchment paper lined baking sheet and dry in 200°F oven for 10-15 minutes, checking often as not to burn, but dry out (shake pan to move lemon zest around).