Depending on the quality, Tonkotsu Ramen restores 30/32/34% of Max HP and an additional 600/1,250/1,900 HP to the target character. Like most foods, this can not target other players' characters in Co-Op Mode.
Tonkotsu Ramen is a type of ramen noodle dishes, whose soup broth is based on pork bones (Japanese: 豚骨tonkotsu). The reason this dish was chosen to appear in the game among various kinds of ramen is likely because it is the most popular Japanese ramen dish in Mainland China.
Although the English text specifically uses the term tonkotsu which means pork bones, both the Chinese and Japanese versions refer to this dish just as "Beast-Bone Ramen" (Shòugǔ Lāmiàn (Chinese: 兽骨拉面) and Juukotsu Raamen (Japanese: 獣骨ラーメン)).