A mix of fresh hot pepperscayenne, serrano, jalapeño, and bell peppers are all staples, but any hot peppers work. Expect to need 50+ hot peppers to return 1 cup of crushed red pepper
Cut the tops off of the hot peppers and lay them out evenly on a cookie sheet.
Place them in the oven on low heat to dry them out. This can take 4 to 6 hours, so monitor the chilies to make sure they don't burn.
Place the dried chilies in a food processor and pulse grind them until they reach the coarse texture you prefer.
There are alternative methods to drying chili peppers like food dehydrators and even hanging the chilies in sunlight for a few weeks. They work too, but the oven is the quickest, most universal method around. Try mixing and matching hot peppers for unique twists on the traditional crushed red pepper mix. For a milder batch, opt for milder hot peppers. For a spicier batch, lean on the hotter end of the pepper scale.