Over the past few days I've had the pleasure of interviewing two inspiring, if disparate, people - Eleanor, Duchess of Argyll, and the composer James MacMillan - and they have brought it home to me once again that food and the arts are inextricably linked.

Eleanor, nee Cadbury, runs the Best of the West music festival that took place in the grounds of her home, Inveraray Castle, over the weekend and featured top Celtic bands Capercaillie, Skipinnish and Skerryvore. Serving food and drink sourced ­specifically from Argyll is, she said, de rigueur, because visitors to the festival from all over the world as well as from Scotland expect it. That much-used word, provenance, holds ever greater sway in an increasingly globalised food and drink market: Jamie Delap of Fyne Ales craft beers near Loch Fyne described it as "seeing the loch, the hills and the sky and tasting the water from the burn with every sip". The word terroir (soil, or land) goes hand in hand with provenance: Argyll & Bute, a vast area stretching from Mull and Oban to Campbelltown, Islay and Gigha, is blessed with natural beauty, and its seafood, halibut, venison, lamb and cheese are prized because of the unique qualities of the water, soil and microclimate in which they grow. The Food from Argyll collective is extremely pro-active in getting that message out.

It neighbour, the Ayrshire Food Network, incorporating Arran, is equally evangelistic; the famous Ayrshire Tattie is currently in the process of gaining a Protected Geographical Indicator.

As far as I know, the sweet Cumnock Tart has not yet gained such status. Truly a forgotten jewel in the crown of culinary East Ayrshire, it's about to experience a renaissance thanks to James MacMillan, of all people, during his music festival The Cumnock Tryst, which debuts in October.

The rhubarb and apple tart, made with short cold-water pastry, is glazed with sugar syrup and baked four times to produce a sticky, shiny top. The size of an individual meat pie, it was a feature of my childhood teatimes (my father was from Auchinleck and we spent much time in Cumnock - both former mining villages) but seems to have disappeared. James MacMillan told me he has ordered several hundred of them in a dinky canape size for his guests at the Cumnock Tryst. They will be made by Pathhead Bakery in New Cumnock, which currently sells some 300 of them a week to local people. The composer, who was brought up in the town, hopes his support will help the bakery, and even dreams of starting a local food festival during the Cumnock Tryst in future years.

What other foods, then, are local to Cumnock? Pathhead bakery's co-owner George McLatchie tells me his mince bridies - made with proper flaky puff pastry and containing no steak pieces or carrots - "seem to suit" his customers. And his "proper" potato scones are popular: thin enough to roll up in the traditional way, not like the modern thick versions that are made for frying, they sell "by the square mile" at his shop.

Small steps, but a musical tryst with the Cumnock Tart is a pretty good start.