The main ingredient in a traditional shepherd's pie is minced meat, typically lamb. The dish is a classic British comfort food that consists of a savory filling of minced lamb, cooked with vegetables such as peas and carrots, and topped with a layer of creamy mashed potatoes. The dish is baked until the top is golden and the flavors are well combined. Shepherd's pie is distinct from cottage pie, which is made with minced beef instead of lamb. It originated as a way to use leftover meat and is beloved for its hearty and satisfying characteristics, making it a popular meal worldwide.