I love crumble. A decent crumble is a series of contrasts. Texture, taste, tone – all three are complemented by the addition of a bit of creme fraiche which brings temperature and luxury to the party. My grumble with crumble is that so many of them skimp on the crumble and don’t do contrast. If you make a crumble with rhubarb and ginger, you can afford to leave the base mixture pretty tart. To contrast that, the crumble can be nice and sweet. The crumble has to crumble too. That could be another grumble.