Reference for Chullin 216:27

עד שתתן טעם ברוטב ובקיפה ובחתיכות אמר רבי

For it was taught: If a drop of milk fell on a piece of flesh, as soon as it imparted a flavour to the piece, the piece itself is forbidden as nebelah, and it will in turn render all the pieces [in the pot] forbidde for they are of like kind: so R'Judah.

Jastrow