Halacha (Jewish Law) tells us that when food is cooked in a pot, that pot absorbs the taste of that food (to what degree is impossible to know). When that pot is then used to cook something else, the taste that was previously absorbed in the pot is now released from the pot into the food. See here for more background information.
My question is, is this idea exclusive to halachic circles? For example, are there chefs who will never cook one type of food in a pot that was used to cook another type of food, because the taste mixture will ruin the cooking food? Alternatively, are there chefs who specifically choose to cook with certain pots because the flavors that have been previously absorbed in those pots enhance the food being cooked? (I remember a TV comedy that had a similar idea.)
I'm asking because I'm looking for a good analogy/example I can use to explain to non-jewish people why we need to do Hagala (purge flavor by boiling) on a non-Kosher pot before we can use it.
As a parallel, after I read this article, I started using allergies as an example of why just cleaning something is not enough. From the article:
“It’s heartbreaking,” he continues. “My wife and I are brought to tears regularly because Brianna can’t go to her little friends’ birthday parties and have cake and ice cream and everything that they get to have. We can’t really go out and have a meal anymore, because people at restaurants just aren’t aware enough of the severity of it and what it takes to cause a reaction. They don’t understand that if a surface was used to prepare something that had dairy in it, no matter how well you clean that surface, those proteins are still there. And if you prepare my daughter’s food there, she’s going to have a reaction.