1. Start by dry-toasting cumin seeds separately for about 30 seconds (see more below).
2. After that you can toast all the remaining spices together for 2-3 minutes until they start to brown and you can smell the fragrances. If you want to be meticulous, follow the time ranges below (how long to toast Indian spices) by adding mustard seeds first. Then, after a few minutes tossing in coriander and fennel seeds followed by cardamom and caraway seeds a minute later.
3. Finally, let the seeds cool completely before you grind them with mortar and pestle or with grinder.
4. Store the ground spices in airtight jar or container and consume in a few days.

How to dry-roast Indian spices

The best way is to toss whole spices in a dry skillet, stirring and tossing frequently over medium heat, until they begin to smell toasty and fragrant.

1. First, put your spices in a small skillet or dry (no oil) frying pan over medium-low heat (until it is almost too hot to touch), and shake the pan occasionally or stir with wooden spoon to prevent burning. They may pop and jump a bit. The spices are toasted when you can smell their aroma. Make sure not to overheat the skillet as the spices can burn easily. Burned spices will taste bitter.
2. Once the spices just start to darken, transfer them to a bowl and allow them to cool. Their residual heat will keep the cooking and toasting process going a little but longer – you’ll here them sizzle in the bowl.
3. Finally, grind the cooled spices with a mortar and pestle or a dedicated spice grinder.