Heat the peanut butter in a large stock pot over medium heat until melted, about 5 minutes. Stir beef stock and tomato paste into the the melted peanut butter. Add stew meat, increase heat to high, and cook until the beef is browned, about 5 minutes. Reduce heat to low and cook at a simmer until the beef is cooked through, about 15 minutes more.
Stir peas, onion, banana quash, chayote squash, carrot, allspice, nutmeg, pepper, salt, and bay leaf into the beef mixture; bring to a simmer and cook until the vegetables are tender, about 20 minutes.