Tian bu la are Taiwanese fish cakes made with a thick paste which incorporates mild white fish fillets, eggs, and potato or tapioca flour. The generously seasoned mixture is piped directly in the sizzling oil, then deep-fried until golden brown.

The fish cakes are usually shaped in long and thin cylindrical forms, but they are sometimes flattened into thick, round discs. Even though they can be eaten immediately after frying, the Taiwanese traditionally boil them on low heat in a soy-sauce-based broth, which allows the crispy skin to soften, and the cake to infuse with all the pungent broth flavors.

If it is served as a crispy treat, it is usually skewered and enjoyed as a snack on the go. Fried and boiled versions are usually offered in traditional Taiwanese eateries alongside other deep-fried treats such as fish balls or tofu. They are served in bowls and smothered with a sticky brown sauce made with chili paste, soy sauce, miso, and sugar.

Traditionally, the sauce leftovers are later mixed with the broth in which the cakes were boiled in order to create a flavorful soup eaten at the end of a meal. Both tian bu la varieties are staples of Taiwanese night markets and one of the favorite Taiwanese street food items.