Chili powder is basically Roasted dried peppers, cumin, garlic and oregano. I also use it for Carne Asada and salsa.
Recipe:I use whole cumin seeds and toast them a little in a pan, then grind them. I used a dedicated burr or blade-type coffee grinder at home, but employ a mortar and pestle when in competition.
1 tbsp ground cumin seeds
1 tbsp garlic powder
1 tbsp oregano
Actually I start with that and adjust to taste. Stay tuned for more specifics on how much exactly to add. I am experimenting with using a lot less cumin in the base powder and adding fresh ground towards the last half hour to give it that magical taste and avoid the bitterness.