The general rule is about 45-60 minutes per pound at 350°F. I prefer to cook mine at a lower temperature (300°F), so a 3-pound roast will need a solid 3 hours in the oven after being seared on the stovetop.Regardless, always check the internal temperature to ensure doneness. Beef roasts should reach a minimum temp of 145°F in the center, then have time to rest before serving. That said, you'll get the most tender meat if your oven beef pot roast gets closer to 195°F — it won't shred properly until that point!