그 나물에 그 밥이다: two peas in a pod, two of a kind.

나물: greens, seasoned vegetables

밥: rice

→ Same greens, same rice.

→ It’s an expression you say when describing similar things/people that you can’t really tell the difference between them. However, people say this expression in negative situations as well because of its nuance nowadays – ex) 그 나물에 그 밥이라더니, 둘 다 문제아다 (They’re two peas in a pod – they’re both troublemakers.)

→ Similar expressions: 끼리끼리 논다 (kind calls to kind)