Despite every effort, my roast beef came out overdone, only faintly pink in the center. It’s edible, not great. Anything I can do to make it more palatable, other than hot roast beef sandwiches with gravy? Of course there’s a ton of it left over….shepherd’s pie, maybe?
I’ve found that a good gravy, made from the drippings of the roast, can cover a multitude of sins.
Slice as thin as you possibly can.
Pull apart a slice with 2 forks.
Make Tacos 
The salsa adds moisture and helps dry meat.
Another option is barbecue.
Shred the roast beef into a casserole pan. Add your favorite bbq sauce and mix well. Store in fridge overnight. Heat in 325 F oven the next day.
It could help adding oil to the bbq sauce. It needs to be thinned. Don’t glop on a thick sauce. That won’t soak into the dry meat.
Shredding the meat with 2 Forks makes adding moisture more effective.
This reminded me of a YouTube video, where the customer calls the waiter over and complains that the steak is overdone. When the waiter says that he will bring the customer a new steak cooked properly, they say “I don’t want a new steak. I want this steak cooked right!”.
Why not make hash?
I grew up eating slow-cooked pot roast. My grandmother wanted it to pull apart with a fork.
It is delicious, but people today would complain it’s over cooked.
Maybe make a soup out of it. A nice hearty beef barley, perhaps?
Well, the first step is to cook it a little longer to get rid of that remaining pink.
Nobody should complain about pot roast being overcooked (thought it is possible, it takes some effort to do so) because it’s usually made with a cut of meat that is supposed to be cooked well beyond well done temperatures, slowly. Usually to 195-205. This is a different cut of meat than something like standing rib roast, which cooks fine to temps like 130. You wouldn’t want to roast a chuck roast to 130 and expect it to be edible (unless you sous vide it or something, but that’s not roasting.)
Another vote for soup.
BBQ sauce and hamburger buns.
Pulled beef. A good BBQ concoction,either purchased or prepared. Shred the meat. Heat and mix well, serve on buns.
BBQ sauce cures lots of boo boos in meat.
The worst cuts can be made edible.
As @silenus says. Don’t think too hard about it.
Find a good broccoli and beef stir fry recipe. Slice it thin, but don’t add it until the end (the recipe will tell you to use raw meat), because the meat is already cooked. Serve over rice. Good eats.
My dog wanted me to inform you that it’s still possible to put the entire roast to a perfectly good use, where it will be well-enjoyed.
Some good suggestions here. It will never be as good as a properly done roast (IMHO, medium-rare) but it can be quite edible if re-hydrated. One way to do that if served in the ordinary way as roast beef is with gravy. Since it’s past the point of making gravy from the drippings, I’d use a good packaged gravy mix like Knorr Hunter gravy (or an au jus mix if you prefer, but I quite like the hunter stuff.) Yorkshire pudding loaded with gravy helps, too.
Shepherd’s pie is another good option, and I like the broccoli and beef stir-fry idea (but be careful not to overdo the beef even more in any of those cases).
The roast beef subs I buy sometimes are always made with overdone roast beef, I presume because proper medium-rare roast beef has a very short shelf life. But if you can find some good subway buns (or failing that, just some good hamburger buns) you can make some nice sandwiches after brief nuking (only just enough to warm the beef) and slathering with Dijon mustard. Or you can make traditional hot open-face roast beef sandwiches covered with the aforementioned hunter gravy served with fries or mashed potatoes and, if you like, some hot horseradish.
And finally, as @Chronos suggests, bless his canine-loving heart, if there is a dog in the household I’m sure he won’t complain!
I’m traveling so unfortunately cannot access the dendeng recipe I would suggest. It’s an Indonesian beef jerky from Charmaine Solomon’s Complete Asian Cookbook. It even says at the beginning that it’s a great way to use up a disappointing piece of meat. You cut in in chunks, marinate it in soy sauce, palm or brown sugar, and various spices and flavorings, then spread on a tray and cook for a while. It’s an amazingly tasty snack and keeps forever in the fridge.
You could try a variation on bokkeumbap, a Korean dish. Cut the beef and whatever veggies you have into small cubes and stir fry with rice. Depending on your taste, you can add gochujang or soy sauce or kimchi. A fried egg on top is a good addition. It works because it actually tastes better with well done beef.
Yes, if you add enough of a strongly flavored sauce that you don’t much taste the meat, it will be okay. I gotta say, i think beef with broccoli is a lot better if the beef isn’t overcooked, but it’ll be okay with overcooked beef.
And chopping it up and adding it to soup will be fine.
My mother used to make roast beef hash. OMG i hated that. It tasted so strongly of reheated, overcooked beef. If you try that, at least use a lot of onions to reduce the development of that “reheated” flavor.
[heresy]
Having been brought on a grazing property where the chefs were all “members of the royal society of burnt bull”, I’d say that was a well cooked roast.
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Yes, I know beef on the hoof bleeds, I’ve chased my fair share around the property, performed all aspects of animal husbandry for their management and health and butchered them too. Just not on my plate, by preference.