Gather all ingredients.
Mix mice, rice, onion, salt, garlic, egg replacer and black pepper thoroughly in a bowl with your hands until well combined. Roll mixture into roughly 3cm long meatballs.
Prepare tomato soup with stock and soy milk as per tin instructions. Add Wostershire sauce and reduce heat to medium-low. Cover and simmer until meatballs are no longer pink in the center and rice is tender, about 30 minutes. Stir in more stock if sauce becomes too dry.
