I'm having trouble converting the chili recipes I find to use something other than of-the-shelf chili-powder. Thanks to a simply wonderful local spice shop, we have several different kind of chili-flakes. We've already learned that grinding them and substituting 1:2 with powder is ("$@$^@ ow, pass the milk") not correct. What is the ratio-neighborhood we should be exploring for this substitution?
Chili powder is typically a blend of ground chilies and other spices (and maybe even herbs).
I'd go with a blend of:
You can also try mixing in onion powder, other chilie powders, and black pepper. Some pre-mixed blends also include salt. If you have access to other dried chilie powders, you might consider using ancho or new mexico chilies for a 'dark' chili powder, as opposed to the more red powder you'll get from the cayenne. (but cayenne's more available)
Search online for recipes -- you'll find lots of variation out there.
Coriander, cilantro, and sage are more standby's for a good chili powder as well. Nanami-togarashi is an asian chili powder with a citrusy flavor from lime [peel?]. Also, dont be afraid to get some sinusy piquant goodness in there with a little ginger or mustard or turmeric (only a pinch or it may get closer to curry).
You may also like to source the chiles you are using. You may find that getting a dried tien tsin (the hot peppers from asian cooking) and a dried bell pepper, and milling these with a mortar and pestle is a good way to play with the spectrum of spice in your powder.