A bowl of sweetcorn was both food and a cooking ingredient. It could be made by using a bowl on a cooked sweetcorn; this did not require a knife, nor did it provide any Cooking experience. As food, when eaten, it provided healing identical to cooked sweetcorn. A bowl of sweetcorn was called "Sweetcorn" in-game, both at the Grand Exchange and while in the inventory. This created confusion among players as raw sweetcorn has the same in-game name.
Its primary use, though, was as an ingredient in making tuna and corn. At level 67 Cooking, with a knife in inventory, members could use a bowl of sweetcorn with cooked tuna to create tuna and corn. This mixture healed 130 Life points when eaten, but was usually added to a potato with butter at level 68 Cooking to create a tuna potato that heals 220 Life points.
Potatoes, toppings, and ingredients