Crock-Pots are synonymous with long braises and slow stewing -- cooking methods that hold meat above 210 degrees Fahrenheit for several hours -- but if you monitor the internal temperature of a roast, you can remove it when it reaches medium rare, or 130 F. A significant amount of connective tissue melts away as the temperature climbs, too, because it takes a couple hours for a Crock-Pot to reach maximum temperature. Tender cuts offer the most palatability when cooked to medium rare, so go with a roast taken from the loin or the rib section for best results.
Warm the roast to room temperature in a shallow dish lined with a paper towel to absorb moisture. Beef needs about 30 minutes per pound to warm from refrigerated temperatures to room temperature, not exceeding 2 hours.
Salt the roast when you set it out to warm. Simple coarse salt makes a significant impact on tenderness if you apply it to beef early.
Sear the roast on all sides in hot oil on the stove, if desired. Beef doesn't brown in a Crock-Pot and, although optional, stovetop searing before cooking improves the roast's texture and flavor.
Place the roast in the Crock-Pot along with about 1 cup of stock, broth or water. If you want to add vegetables, such as mirepoix, or diced carrots, onions and celery, or pungents, such as crushed garlic, do so now.
Insert the probe of a digital leave-in thermometer in the center of the roast and place the temperature display outside of the Crock-Pot. Secure the lid on the Crock-Pot. The heatproof cable between the probe and the temperature display shouldn't interfere with securing the lid; the cables are thin, shielded and flexible. However, if the cable prevents the lid from sealing the Crock-Pot completely, wrap a piece of plastic wrap over the seam between the lid and crock to prevent steam from escaping.
Set the Crock-Pot to "High." If your model of thermometer has an alarm that alerts you when it reaches a set temperature, program it to notify you when the roast reaches 130 F.
Cook the roast until it reaches an internal temperature of 130 F, or about 2 hours. Take the roast out of the pot and let it rest for 5 minutes before serving.