Be sure to read pressure cooker manufacturers directions before beginning.
Heat oil in pressure cooker over medium-high heat with the top off. Add pork; brown on all sides, turning, about 10 minutes. Remove pork roast to platter.
Add onions and garlic to pressure cooker; saute until lightly browned, 3 to 5 minutes. Stir in chili powder, salt, cumin and cayenne; cook 1 minute.
Stir in the crushed tomatoes and water. Add pork. Place lid on top of pot and lock.
Place cooker over medium-high heat. Once cooker has reached pressure, lower heat to maintain pressure and begin timing; cook for 20 minutes. Remove from heat; release pressure. Cool pot down; remove the lid. Add carrots, red pepper and potatoes. Place lid on top of pot and lock. Return to heat. Bring up to pressure; cook for 10 minutes. Remove from heat; release pressure. Cool pot down; remove the lid.
Add thawed peas to pot; stir to heat through.
Remove the pork roast to a platter; cover with aluminum foil to keep warm; let stand for 10 minutes. The internal temperature should register at least 160 degrees F on instant-read thermometer.
To serve, arrange vegetables around meat on the platter. Spoon on the tomato sauce from pot. Garnish with cilantro. Makes 6 servings.