These chiles are often sold in cans, swimming in adobo sauce. If you don't use up the entire can at once, refrigerate the leftovers for up to one week, or freeze them. When you want to use those ...
Wash the chipotle chillies, remove the hard stems (leave the seeds in) and place them in a bowl. Pour over 150ml/5fl oz just-boiled water, cover with cling film and soak for about 20 minutes.
You can buy chipotles in adobo (or in a tomato-based sauce) in a tin, or you can buy them dried from online retailers and make your own paste. A homemade paste will pack far more punch as you will ...