This is the 2493rd most frequent Japanese word.
出来上がっ
"出来上がっ" means "finished" or "completed."
出来上がった is used here to indicate that the project has been entirely finished or completed.
このプロジェクトがようやく出来上がった。
This project has finally been completed.
出来上がっている describes the state of the painting as being completed and refined.
彼女の絵が見事に出来上がっている。
Her painting is impressively completed.
出来上がった refers to the completion or readiness of the dinner preparation.