It's surprising how often that little store cupboard standby has come to the rescue of a mundane recipe. Of course, only the larger Waitrose have it in stock although you can get it online from Ocado.
We're lucky up here in the rural Wolds - we can get it fresh from the Farmers Market in Louth on a Wednesday (that said, Simian Simon, the local monkey chuckler has been in Magaluf for the last couple of weeks so there's been no fresh while he's been away. No doubt he'll be in a hell of a mood when he gets back till he's caught up again.)