Reuse frying & sauce pans multiple times during cooking session

I think thermal shock is unlikely to be a problem at the temperatures you're likely to use. I had heard that it is mainly a problem if the pan is very hot (500 degrees or more, although some materials like cast iron are more susceptible to thermal shock than others) and if the shock is very great, like plunging the whole thing into cold water.

I wouldn't even think about thermal shock at temperatures cool enough to be cooking with - if the water is sizzling and dancing on the pot, that's the test for it being ht enough to cook, and adding room temperature food or liquid for de-glazing are well within the expected ranges for temperature, and probably as much of a temperature difference as you're getting when rinsing your pan. If your food is done cooking, and cool enough you can put it into plastic without worrying, the pan it's cooked in and that has been off the heat while you're scraping the food out will probably be cooled enough not to crack from being run under water.

As a side note, I once had a pan crack from thermal shock - it did not shatter, or blast pieces everywhere, but spluttered a lot of steam and sharply cracked nearly in half to let it equalize the thermal stress. It is not pleasant, but it was not quite as terrifying as "blasting pieces" makes it sound.

As for residues, I personally wouldn't worry about them too much - since very little will stay in the pan after being rinsed off, and they should have already been cooked to safe temperatures, the pan doesn't sound like it will be sitting out between sessions long enough to breed anything dangerous (which would be hours), and the next batch of food should be cooked to safe temperatures again. I would be more concerned about flavor contamination than safety, although different people tolerate different levels of risk.

Metal pots and pans are built for heat then be cleaned. At worse it might crack. It would not blast metal pieces everywhere.

If you add the water slowly you will introduce less thermal stress.

I would even consider a high heat silicone scraper and go right back to the stove.

As no one's touched on the health aspects --

• If the first item is finished cooking, you'll be fine. The only serious problem would be partially cooking meat and then cooking something that doesn't have to be cooked to high heat. (although this is mitigated if you sufficiently heat the pan between uses ... but maybe not along the sides).

• If you're cooking for someone with food intolerances, you might want to give it a more thorough clean between dishes to prevent cross-contamination ... but if they're a full-blown celiac, just having used flour in the kitchen might be enough to give them problems.

Personally, I've been known to deglaze my pan (pour in a little water, then scrape up any browned bits on the bottom), dump it out, and then just give it a quick wipe-down with a paper towel before starting the next item -- so it's basically what you're doing, only using a wooden spatula instead of a brush.

As it sounds like you're using a non-stick pan, you won't have much (if any) browned bits to scrape up, but if you aren't and want to make a sauce for the first item, you can deglaze with more flavorful liquid (stock, wine, etc.) and possibly add some butter to it.