Generally, I do it in two and half. More than four I'm disappointed in myself and I'm not allowed a Jaffa Cake. My best ever is one thirty-two, and obviously the full on Bakewell tart ambition is under ninety seconds. You'd have to be seriously in the zone to manage that. You'd have to be, as we say in our house, kipling it.
This is not a stealth brag, by the way. There's nothing stealthy about it - unless it turns out that everyone else is banging in the bakewell daily, in which case I shall retire from public life.