If your tomatoes are hard and dry like the ones I use, soak them in a little water to soften them for an hour. click here to start a 1 hour timer
If your tomatoes are already soft, add them straight into the bowl
My chicken was raw, so I cooked it in a frying pan with a little oil. Once it was done, I chopped it into little bits and scraped all the pan juices into a large plastic jug, along with the chopped chicken.
Now use a stick blender to whizz it to a smooth paste, adding the tomato soaking water if you need it to go to a paste, or some of t he oil from the jar, depending on what you used.
If you don’t have a stick blender, try grinding it with the bottom of a rolling pin, or similar, in a big mixing bowl. You’ll probably have to let the tomatoes soften really well first.
Put into a jam jar or lidded container and keep in the fridge for up to a week. Longer than that and you will need to freeze it
Notes
The finished paste filled a jam jar and when I weighed it (excl the jar) it was 250g, so 12 sandwiches using a 20g tblsp per sandwich with two slices of a value wholemeal loaf, 2p, that's 7p a sandwich.Preserved lemons may be hard to find. You can make your own easily enough, but they wouldn't be ready the same day. In their absence, try a squeeze of lemon juice, and/or a grating of lemon zest