Refer to the passage below and then answer the question afterwards in the same language as the passage:

Passage: Although it is known as a "pineapple bun", the traditional version contains no pineapple. The name originated from the fact that its sugary top crust is cooked to a golden-brown color, and because its checkered top resembles the epicarp of a pineapple.

Question: what is the known nickname?
pineapple bun