Heat oil in a large pot over medium-high heat. Cook and stir beef cubes in hot oil until browned on all sides, about 10 minutes. Add onion and garlic to beef; cook and stir until slightly tender and fragrant, 3 to 5 minutes.
Stir water, tomatoes, okra, tomato puree, coriander, cumin, allspice, lemon juice, salt, and pepper into beef mixture. Bring to a boil, reduce heat to low, and simmer until sauce thickens, about 2 hours.