When you combine them, `特色 (tèsè)` means “unique characteristic” or “special feature”. Adding `菜 (cài)` at the end specifies that you are talking about a dish with unique characteristics—a specialty dish.
In Chinese food culture, a `特色菜` is a source of immense pride. It's not just a dish; it's an identity. For a restaurant, it's their reputation on a plate. For a region, it's a piece of their cultural heritage (e.g., Peking Duck in Beijing, Soup Dumplings in Shanghai). This concept differs slightly from the Western “house special” or “chef's special.” While a “house special” might be a temporary promotion or simply a popular item, a `特色菜` is a more permanent and profound statement. It is the dish the establishment believes defines them. Asking for the `特色菜` is seen as a sign of respect and genuine interest. It tells the host or waiter, “I trust your judgment and I want to experience the best, most authentic food you have to offer.” In a group dining setting, a Chinese host will almost always order the restaurant's `特色菜` for their guests to show generosity and ensure they provide a high-quality experience, a concept related to giving face.
`特色菜` is one of the most useful terms a foodie or traveler can learn.
The term is neutral and used in both formal and informal dining situations.