How to recook a roast?

Question

I bought a chunk of vacuum packed beef from the discounter. The label said "roast meat", and didn't indicate which cut of beef it was. It was lean meat (4% fat), but that's normal in Europe.

I roasted the meat with some glaze, at 175°C, until the probe showed 63°C. Then I seared the crust on a 320°C iron pan. It turned out somewhat rare (I suspect the probe isn't good enough), but still looked like a perfectly good roast. But when I started eating, I discovered that the meat has enough connective tissue to be practically unchewable in this state.

Now I want to recook the meat and eat it. My first idea was to make goulash, in chat I got the advice to make a stew. The point is, while I know that theoretically it should work, I've never recooked meat, and I don't know if there are some details I'm overlooking. Also, is there a special kind of stew particularly well suited to my case?

Is there something special about making a stew or a goulash with precooked meat, different from using raw meat? Am I forgetting something here? How long should I cook the meat? (Assume that I start measuring after the center of the meat pieces - whatever size - has reached 68°C). I have roughly 20% to 25% connective tissue, the thickest fascia are maybe 3 mm. The meat is already roasted, seared, rested and cooled (and will be refrigerated when I start recooking).

You don't have to explain the food safety implications, I am aware of them. Just assume that in this case, I am willing to take the risk of eating the recooked meat.

Edit I am not all that interested in recipe suggestions, I guess a common stew will do. What I want is to know how the usual technique of slow cooking changes when the meat is precooked, and if somebody has already done this and can confirm that it works. By the way, the meat is now cut in chunks and marinating in the fridge.

Answer

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.

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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.

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