Date: 1 Tishrei 5662
From: Rabbi Mordechai Leib Winkler, Mad
To: The Beit Din of Grosswardein
The responsum discusses the halachic status of bread where there is a concern that forbidden fat was mixed in, but a majority of the fat is kosher, and the principle of not nullifying a prohibition intentionally.
Source: Yoreh Deah I §52