Had to go for good old potatoes - just so much you can do with them.
Although are they really vegetables? They're actually tubers, and don't count in your 5-a-day.
New topic idea - besthing to do with potatoes:
Boiled
Roasted
Fried
Chips
Skins
Crisps
Have to say I love some good roasted, crispy on the outside, light and fluffy inside