Ok, I am only a home cook -- and not a chef by any means so please excuse me if my question is in any way dumb.
I have a humble, unpedigreed, stainless steel chef's pan that I have used for app 3.5 years. I use it to make curries and stews mostly. I always use wood or plastic utensils. I always oil the pan thinly and heat slowly, then either saute my onions + spices or brown meats, then add liquids and and allow everything to simmer for 1-2 hours depending on dish. It has always heated seemingly evenly and allowed me to leave it unattended for at least 30-40 mins if I add enough liquid and low heat. Also, the food release was very good -- even after making rendang (beef simmered for 3 hours in grated coconut will fairly dry) the pan would be clean without my ever having to scrub it. Nothing stuck to the bottom if there was at least a couple millimeters of liquid there.
I was very happy with pan till a couple months ago -- food began catching/sticking on the bottom of the pan -- I would have to check and stir more often etc. I gave the pan a rest for about a month (lol to use fancy new Calphalon), but began using it yesterday. Now I find it's worse -- food was sticking within a few minutes. I sauteed a curry paste of onions/garlic/ginger/grated coconut in some oil and it was sticking constantly. Then I added liquids to simmer and found food sticking every 10 mins. For the first time in 3+ years, I had to soak the pan because there were little brown bits that didn't release when I washed it.
My question: why is this happening? What has changed this pan? Is it something I have done gradually? I did sometimes let my housekeeper wash the pot the morning after -- should I have made sure to watch what she did? It was so easy to clean....
It was only a 25$ pan at best -- but I am curious to know what kinds of things might possibly change a pan so that I can avoid this in the future.
Thanks in advance, to anyone who reads this and answers,