1. From a chip shop - Just salt and vinegar (plenty of both)
2. From MacDonalds etc - Sweet and Sour sauce and/or ketchup
3. Cooked at home salt, vinegar and ketchup
Chips and grated cheddar RULE - although a good chip butty w/ plenty of butter takes a lot of beating. Maybe a chip/cheese/butty, although that could be ruining the simplicity ...
Putting ketchup on chips ruins them, and should be punishable with a hundred lashes. At least.