Pale and interesting, forced rhubarb is gradually returning to favour after too long an absence. We are at the end of the season for the shed-grown delicacy from Yorkshire, but for those who have forced their own, now is the hour of discovery. Remove all the covering material, reach down to the base of a shoot and pull gently but firmly. No need to cut: the slender, shiny pink thing comes away entire in your hand. Crumble, certainly, but custard or cream? I wonder.