Steaming something - remembered that a pinch of cream of tartar in the boiling water stops the pan turning black (Mrs Beeton?).
Knew there was a little container of it in the top cupboard, with the flour and baking powder, as it used to go into an excellent recipe for scones, which has not been made for a while, because of the amount of butter needed on a fresh scone. And when you make a dozen, they all have to be eaten while they're fresh, don't they?
Found the little drum, put in the pinch of powder, went to return it to the shelf, noticed the "Best Before" date.
When we moved, five years ago, didn't we check all the stuff coming out of the old kitchen and going into the new one? Really is it so long since I used to do home-made scones? Have I gone back to hoarding stale ingredients?
It was dated Feb 98.
The new container I bought this morning is dated Aug 08. You never need more than a teaspoonful in a recipe, but I don't suppose it will get used up any quicker than the last one. Unless I start baking scones again ......