New Mexico chile powder is made up purely of dried chiles (as opposed to standard "chili powder," which is actually a mix of ground chiles with several spices like oregano, garlic powder, and cumin. It has a moderate heat level with earthy and fruity undertones. It is commonly used in enchiladas, sauces, and ground beef taco filling.
Substitute crumbled dried New Mexico chiles, or, for a slightly different flavor profile, another pure chile powder, such as ancho.
Store in a cool, dry place.