Trim fat from meat. Cut meat into eight equal pieces. In a small bowl, combine cumin, paprika, garlic powder, pepper, and salt. Sprinkle mixture evenly over meat pieces; rub in with your fingers. In a 6-quart pressure cooker, heat oil over medium-high heat. Brown meat pieces, half at a time, in hot oil, turning to brown on all sides. Remove meat from cooker; set aside. Drain fat from cooker. Cool slightly.
Add stock to the cooker. Add the cooking rack to the cooker. Place meat pieces on the rack. Lock lid in place. Bring to pressure over high heat; immediately reduce heat to stabilize and maintain pressure. Cook for 25 minutes. Remove from heat; set aside to depressurize cooker.
Transfer meat to a serving platter. If making Beef & Noodles (see associated recipes), reserve cooking liquid. Slice meat or cut into chunks to serve.
Tip: Use the leftover roast beef to make Shredded Beef Tacos, Barbecue Beef Sandwiches or Beef & Noodles (see associated recipes).
To store meat: Divide meat among airtight containers. Cover; seal. Refrigerate for up to 3 days or freeze for up to 3 months. If frozen, thaw overnight in the refrigerator before using.