Here's what I do when I'm working at home:
Take a nice 7-bone roast with good marbeling, season it and coat it with flour. Brown it on medium-high in a large, cast-iron skillet.
While the roast is browning, heat a kettle of water to boiling.
After the flip side has browned, turn the heat down to medium-low and add the boiling water. (A can of beer doesn't hurt.) Fill the skillet with water right to the top of the roast. Place a loose-fitting lid (I use the flat lid to a large aluminum pot) atop the skillet. Let the roast simmer, turning once, for two hours. If the water runs low, add more.
After two hours, take off the lid and turn the heat up a notch. Add a couple of quartered yellow onions, fitting them into the pan wherever you can. Cook it for another hour or so withouth the lid, stirring the onions occasionally. The liquid cooks down to a delicious gravy, and toward the end when the gravy is just right, the cooked onions start to carmelize. If it's a good pot roast, it will be flavorful and falling-apart tender.
If it's a really big cast-iron skillet, you can add potatoes and carrots when you add the onions.