Blueberry Tart

Blueberries are plump, cultivated berries, which develop a great taste when cooked. Bilberries are tiny and grow wild in Europe, and have a sharp, tart flavour. The two are sometimes confused because of the similarity of the names. I like to make this tart with bilberries – Tarte aux Myrtilles – which are hard to find but worth it (this is the only thing that motivates me to brave the moors and pick a batch once in a while), but you can use any berry fruit in season; and besides blue