Before we teach you how to tie a roast (we use the word "teach" loosely here), don't you want to know why you're tying up a nice piece of meat in the first place? You don't? You're walking into this whole roast thing totally blindly, trusting that the butcher's twine has some greater purpose you're not even curious about? Good, that's what we thought. Grab some string and let's get into it.
There are two main reasons for tying a roast or any other piece of meat about to go to the oven: the first one is a combination of form and function. When cooked, a piece of meat will expand while heat brings out its juices. Tying it up keeps it from "spreading out," losing that nice round filet shape you paid so much money for. Spreading will only affect its appearance, not its flavor — and tying it up keeps it nice and tight so the juices are more prone to staying in instead of running out.
The second reason is stuffing. Butterflying and stuffing a piece of meat is great and all, but if you reassemble or roll it up and have nothing to secure it, you might end up with a flap of overcooked meat with a bunch of tasty stuffing come out of the middle and sides. That's what we call a fail. So after stuffing that double-cut bone-in pork chop with spinach and feta or rolled up that lovely beef tenderloin, Rosa di Parma–style, all that good stuff stays inside.
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