끝내준다 [ kkeunnaejunda ]
끝내준다 is an inflected form from 끝내다 [ kkeunnaeda ], which means ‘to finish/end /close’.
Among many usages, this expression is interestingly used for something or a situation that is really good.
You can use 끝내줘요 [ kkeunnaejwoyo ] or 끝내줍니다 [ kkeunnaejumnida ] to be polite. To emphasize, you can use 정말 [ jeongmal ] in front of it.
이 음식 끝내줍니다. (This food is awesome)
분위기 끝내주네. (I really like this mood.)
A) 여행 어땠어요? (How was the trip?) B) 정말 끝내줬어요. (It was really fantastic.)