Scotland has many "delicacies". Most of these aren't really delicacies at all, just the result of ingenuity, desperation, and being poor. I blame the English. However, my knowledge of history is poor, so treat that as a piece of humorous no-insult-intended bigotry.
Resembling vomit somewhat in texture, colour, and arguably taste, porridge is supposedly a delicacy in Scotland. However, we don't have some sort of bizarre palate that makes bland, dull food highly desirable. It is, however, nutritious, cheap, and easily available. For poor Scottish farmers in centuries past, it was therefore something of a staple food, and has become strongly associated with this country.
Haggis is similar in a way, as its primary reason for existing is, arguably, because people were too hungry and poor to throw away bits of animal that were technically edible, so to make them palatable came up with the idea of mincing them, putting them in an edible bag (i.e. a sheep's stomach, originally) with some oats and eating them. It actually tastes alright, or at least the ones you get in the chippy do. Think of it as a McDonalds hamburger, but more honest about what it contains.
Whisky is also a Scottish delicacy. It deserves to be. It's an acquired taste, but there are hundreds of varieties, and with the addition of a mixer you're bound to find some form in which you like it. Not that it should be mixed. Ever. That's sacrilege.
Irn Bru is perhaps the least-known Scottish delicacy, at least to tourists. It's a truly wondrous drink, the most manly and amazing soft drink in the world. It's a hangover cure, stimulant, mixer, and you could even dye clothes with it. Maybe. It does stain.