Beef – How to check stew doneness

Generally speaking when speaking of "stew beef", the meat will break down more the longer you cook it. I often make shredded beef for tacos out of that cut by simmmering it for a few hours or more. At 1 hour, I'd say it was undercooked.

For example: http://www.foodnetwork.ca/recipes/Main/Beef/recipe.html?dishid=1772

In there he recommends using stewing beef, browning it first and then "... stew until the meat is tender and can be cut with a spoon. This will take at least an hour and a half."

I'll often do what my mom referred to as 'planned overs', and make too large of a roast for us to eat, then turn the rest into a stew or something else in the following nights.

The only comment I really have is that if you like the 'fall apart tender', I find it more difficult to get the second time around. I recall that Alton Brown specifically cooked the meat ahead of making a stew in an episode of Good Eats, and in checking the transcript of the episode, he said it's due to the behavior of gelatin:

You can see that the meat is very, very soft. It’s almost like pulled pork in there. We’ve had complete collagen to gelatin conversion. But when this cools for an hour, and if we refrigerate it after that, we’ll see that this is going to change. More on that later.

...

Now, what’s really interesting, though, is that once gelatin has reached the gel state, it takes more heat to re-dissolve it than it did to render it from collagen in the first place. And, believe it or not, that is a good thing

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Ahh, the meat is perfectly heated through, but it’s not falling apart. That’s because we let it cool down before reheating, and that is why stews, braises, fricassees, and blanquettes are always better the second day.