Guajillo peppers are a type of dried chili pepper commonly used in Mexican cuisine. They are known for their deep red color and mild to medium heat, typically ranging from 2,500 to 5,000 Scoville Heat Units. Guajillo peppers have a slightly sweet and tangy flavor, making them a popular choice for salsas, sauces, and marinades. These peppers are often rehydrated before use, allowing them to release their rich flavor. Guajillo peppers are a key ingredient in traditional dishes like mole and adobo, contributing to the complex taste profiles that characterize many Mexican recipes.