Chili flakes, also known as crushed red pepper, are made from dried and crushed chili peppers. They are commonly used as a spice to add heat and flavor to various dishes, including pizzas, pastas, and soups. The heat level can vary depending on the type of chili used, with popular varieties including cayenne and jalapeño. These flakes are often found in spice racks and are a staple in many kitchens around the world. They can be sprinkled on food before or after cooking, allowing for easy customization of spice levels. Additionally, chili flakes contain antioxidants and vitamins, contributing to their popularity in cooking.