I have made many a crumble in my life. I would count myself as something of a crumble connoisseur. I cut my teeth on the classics – apple, rhubarb – before graduating into a wild, wonderful world of pineapple, coconut and black pepper, or pear, chocolate and raspberry, or fig, blood orange and hazelnut, even venturing occasionally into savoury variations (tomato, rosemary and cheddar; butternut squash, sage and blue cheese). There is very little that I will not try to crumble, and there is very little that isn’t improved by being smothered in a blanket of butter, sugar and flour, rubbed together into an irresistible nubbly sweetness.