For a deep colour but a not too spicy taste, choose the long shiny thick dried chillies. Sun them till crisp. Break off stalks, and discard. While pounding add a tsp. oil to a kg. of chillies. This will keep the sting of the chillies from permeating the air and everybody's nostrils. (It will also act as a preservative.) Pack in ziplock or seamseal polythene bags. Or in sterile glass jars, with airtight lids. Put small blocks of asafotedia or spread some salt on top of the powder to preserve from getting spoilt for longer time For a milder colour, use slinder, wrinkled skin dried chillies, they are usually extra long