Heat a small skillet over medium-high heat. Toast the spices until aromatic, shaking every few seconds. The coriander and cumin seeds should turn reddish brown and the chilis should blacken in spots.
Transfer to a plate to cool. After the spices have completely cooled, grind to the consistency of finely ground black pepper.
I had a hard time knowing when to stop toasting. The pan started to smoke, so I stopped b/c I was afraid of burning the spices. I wonder if I should have gone a little longer on lower heat though. Or maybe even longer at medium high…
The spice mix was really too hot. I plan to make it again with no chiles, so I can mix the hot with the non-hot spices. Also, next time I make it as per recipe, I'll shake out the seeds (which I didn't do this time.)