go CAREFUL COOKING
[91a middle] Braisa: Since people eat bread with all foods (ie: both dairy and meat), one may not knead dough with milk, nor bake bread in an oven coated with animal fat, to avoid violating the prohibition of eating meat and milk together.
follow site D-E-ep Thoughts: There are many prohibitions that we are very careful of and heavily guard ourselves against, while there are others which may (Chas Vishalom) be transgressed since they are not properly guarded against. All too often, the Yetzer Hara tricks people into thinking that they are on too high a level to worry about simple, low-level prohibitions. We must never let our guards down against any possible Aveiros and keep our spiritual connections strong to Hashem.