Finely dice an onion: very very finely. Teeny tiny pieces.

From two 90g tins of sardines in oil, take out the sardines . Open them carefully along their backs and take out the backbones and any other bones you can see.

Put them in a bowl and mash them up with a fork, add the onion, and the zest and juice of one lemon.

Season and serve on toast.

Jack Monroe: Tin Can Cook, page 112. She says to keep the oil from the sardines, but doesn’t say what to do with it…

If you only have sardines in tomato sauce, those are good mashed up and spread on toast, and you can do the same trick with adding finely diced raw onion to give them a bit of pizazz.