Beef is generally a pretty hard meat to break down compared to other meats. Takes longer to chew, longer to digest, and requires more heat to make it tender during the cooking process. So while a crock pot is fine for most of the operation, you'll meet with the desired success if you'll instead braise your cut of beef in a covered pot (not a pan) on the stove top.
Make sure your pot is of the stainless steel variety, as you'll be going at it pretty aggressively with your metal spatula. And absolutely make sure it has a heavy bottom. Invariably they're a separate piece welded on to the lining of the pot. The bottom of the pot really needs to be able to hold and evenly distribute heat, which is simply not true for pots which by definition are bowl-shaped pieces of sheet metal. Remember, part of what the term "evenly distribute" means is that a balance is struck between the burner and the bottom of the pan. If that bottom is almost non-existent then there's no back-and-forth between the two. The heat just leaps straight from burner to food surface and makes it impossible to do much more than sauté or stir fry.
Add to the pot a thin layer of olive oil, thin meaning just a bit more than one sixteenth of an inch. Set the burner up in the range of medium high to high. (Not high, not medium high, but squarely in between those two.) Just before the oil reaches its smoke point drop in your piece of beef. Your goal is to sear the beef on that side, which will take about 80 seconds. (Do not apply additional pressure to the meat.) Even at that short of a time span it will want to stick to the bottom of the pan. You want to separate the two, but not at the expense of tearing the meat. (Otherwise there's no sense in searing it.) So flip your spatula over (underside facing the ceiling), slide it under an available lip, and then rock it from side to side while gradually pushing it further and further underneath the cut of beef. This means that the flat edge of the spatula retains contact with the bottom of the pot the whole time. Rocking, here, does not mean teetering.
Once the beef is loose, grab a pair of kitchen tongs and stand it up on one side (whichever side is most convenient). You're now going to sear that side. In fact, you're goal is to sear each side of the cut of meat. Generally that would be six sides: two broad, two narrow, and two ends. But trust me, this will make all the difference in outcome. The searing creates much more of a "closed system*, by which the cut of meat is able to stew from the inside out rather, that is, than from the outside in. Stewing from the outside in is synonymous with boiling. Boiling beef draws all the moisture out and leaves behind a mass of tissue. So that's never what you want to do. You want to force the moisture to stay in the beef while it's cooking, at least as much as humanly possible. Searing makes that possible.
Now the meat needs to be braised. It's beef. It needs to be braised. You can accomplish this one of two ways. You can leave it in the pot you started with on your stove top. Or you can transfer it to your crock pot. If you do the latter though, it's imperative that you bring it's temperature way up first. Just add about a quarter cup of water (or beef stock) to it and bring that to a roiling boil. Yes, a quarter cup (not a misprint). Not only is this all you'll need, this is one of those situations where more is literally less. So if you're going to add Worcestershire sauce, make sure that's part of this quarter cup of liquid. Also, when you add the beef you'll want to make sure and include all of the oil (flavors) produced in the first step.
Now, if you're going with the standard stove top approach, while the heat's still up (as before) you just add that quarter cup of water and cover. You'll need a clear lid, because braising by definition entails just barely keeping things at a boil, in which case you'll be needing to see what's happening without changing what's happening. As steam rises and contacts the lid it eventually trickles back down and keeps the level the same. It's this equilibrium you're after. Meanwhile, as the meat slowly releases it's own juices, (emphasis on slowly), that added amount of liquid is sufficient to compensate for any incidental, low-level evaporation. Same thing with the crock pot. When you drop the meat in it'll temporarily stunt that roiling broil. Here's the time you should be cranking the dial down. Your goal, again, is to get it as low as possible without losing sight of slight movement in the water. And then your goal is to keep it that way.
There's no reason to expect this stage to take any less than a couple hours to accomplish, though closer to four is even better. Remember, the beef is being broken down. And I know from experience that patience at this stage reaps a huge dividend in tenderness. You won't have to cut the meat. Nor will anyone to whom you serve it. It'll simply pull right apart.
Now, the vegetables. Always add first the ones that take longest to cook. Remember, you're going to stay here with low temps (just enough to boil water). So gauging what you add (meaning when) can be a bit nuanced compared, that is, to just throwing everything in together into a high heat environment. I always go with celery first. Then carrots and onions. Then potatoes. (You may find it more practical to lightly oil your pieces of potato and then salt and pepper them before adding them to the stew.) And remember, this is the diametric opposite of stir fry. Once the braising process commences, at no point ever will you be doing any stirring. You just add what needs to be added, cover, and allow the process to bring itself to completion. The vegetables will release all of their water. You won't have to add any more. (If you do favor a particularly soupy stew, adding preheated beef stock should suffice, but no sooner than a half hour before serve time.)
With a half hour's prep work and searing, three hours braising, and a final hour to hour-and-a-half for the vegetables to slow cook, your stew should take about six hours to make. But this is not the kind of thing you can crank up like a machine and then come home to after a day at the office. A good stew has to be fussed over in a very present and very hands-on sort of way. A crock pot can work. But it's really just one more step in an already ample repertoire.
