From its name, you might think that the spice labeled chili powder at grocery stores in America is simply ground up chili pepper, similar to cayenne pepper. But this assumption is very wrong, and could easily ruin the dish you are making.
American Tex-Mex style chili powder is, in fact, a blend of spices. Cayenne happens to be one, but the other ingredients—cumin, garlic powder, oregano, and paprika—are much more prevalent. The ratio is one part cayenne to seven parts other spices, depending on the blend.
Just be mindful when you are at the supermarket or spice store looking for chili powder since there are also spices labeled "chile powder." These are made of pure ground up chile peppers such as cayenne, chipotle, and ancho. They will be spicy or simply add a completely different flavor than what the recipe intended.
Chili Powder vs. Cayenne Pepper
Since cayenne pepper is made solely from the cayenne pepper, it is not a chili powder substitute. Ground cayenne pepper is eight times hotter than chili powder. If your recipe calls for 2 tablespoons of chili powder and you use 2 tablespoons of cayenne pepper you won't make that mistake twice as cayenne pepper is pure heat.
Confusing chili powder with cayenne pepper is potentially a worse culinary mishap than using baking powder in place of baking soda. In one case, your cake won't rise, but in the other, your dry rub might burn somebody's mouth off.
Making Your Own Chili Powder
If a recipe you are preparing calls for chili powder and you don't have any, you can make your own. In this mixture, the single most prominent ingredient is cumin. Together, the cumin and garlic powder make up almost half of the ingredients, which means that chili powder is not especially hot. Thus, chili powder alone is not going to be the primary source of heat in your chili or tacos; instead, it adds warmth.
Of course, if you make your own chili powder, you can make it as hot as you want. Bear in mind, however, that some recipes call for chili powder plus additional cayenne, so you might have to make some modifications.
Also, some store-bought chili powders contain salt. When it comes to salt, it is best to control how much goes into a dish independently of the other seasonings. Season your dish with Kosher salt toward the end of cooking. And be sure to taste the finished dish to check for a balance of flavors.
A typical blend of spices to make homemade chili powder would be two or three parts ground cumin, two parts garlic powder, and one part each of cayenne pepper, paprika, and ground oregano. Mix the ingredients together until well blended. Store any of the mix you don't use immediately in an airtight container. If you just want enough for one recipe, the part could be a teaspoon, resulting in about 3 tablespoons of chili powder. If you use tablespoons as your part, then you would get about half of a cup.