It's a square, deep plastic box about 6 x 6 inches and 3 inches deep, no label. Now the frost's melting a little, I can see that it's sort of translucent yellowy egg-white in colour and it fills the whole box to the brim.
I cannot for the life of me remember what I put in it!
As I have also retrieved a plastic tub of pureed spag bol from next to it at the back of the top shelf, I can only imagine it dates back to when I was weaning DD... which was a good 2.5 years ago < slattern>
I know it's not egg-white, because there is no way on God's earth I'd use that many egg yolks on their own!
Any guesses?
(If I let it defrost to tell what it is, I'll have to use it/chuck it and the hoarder in me baulks at such a notion...)