Clean cabbage and tomatoes. Blanch tomatoes, remove skin and cut into slices. Cut cabbage and tofu skin into similar sizes (see pictures). Blanch tofu skin to remove impurities.
In a heated wok, add oil, tomato sauce, salt, sugar and water. Stir. Add cabbage, coat with sauce and allow to cook down. Add tofu skin and tomatoes. Stir and allow all to simmer. Serve.