rice bowl with beef/pork and egg
A pun on 親子丼 (oyakodon, chicken and egg rice bowl). Uses beef or pork instead of chicken, so the meat and egg are 'strangers' (他人), not parent and child.
See also: 親子丼
今日のランチは他人丼にしよう。
I'll have a beef and egg rice bowl for lunch today.
This restaurant's tanindon uses pork.
Standard kanji spelling. The reading たにんどんぶり is also used but less common.
From a pun on 親子丼 (oyakodon). 他人 (tanin, 'stranger') replaces 親子 (oyako, 'parent and child') because the meat is not chicken.