Cut tofu into rectangle 1 inch wide, 2 inches long and 1/4 inch thick. Dry well on paper towel. Heat dry skillet 1 minute. Add oil. Fry tofu over moderate heat to light brown on both side. Remove and set aside. Brown onion in leftover oil for 2 minutes. Add rutabaga, stir-fry 2 minutes. Add tomato, pepper, soy sauce, cumin and salt. Stir-fry 1 minute. Add water, cover and cook 5 minutes. Uncover, add tofu, stir, cover and cook for 3 minutes.