Crumble à la ratatouille

In perhaps the most unlikely and spectacular British culinary putsch for decades, French sandwich bars and supermarkets shelves now carry ready-made crumbles, crumblesque desserts and even yogurts with crumble toppings.

A far cry from the school-lunch nightmares of my childhood, the French versions, produced by applying the principle of a crunchy topping, gradually softening and soaked into by a poached base, can be fascinating. The worst I ever tried had a dark chocolate base. This