Add cumin seeds, coriander seeds and peppercorns to a cast-iron skillet kept over medium heat.
Roast the ingredientsfor 1-2 minutes until toasted and aromatic.
Transfer to a plate and let it cool for about 10 minutes.
Add the cooled spices along with the remaining ingredients to a blender.
Blend to a fine powder.
Storein an air-tight container in a cool, dry place for about 3-4 months.
Notes
If you don't have dried mint leaves, you can easily make some at home from fresh leaves. Just saute them on medium heat for 5-6 minutes to dehydrate them.