Concentrated tomato paste

Sprinkle the tomatoes with the salt and place them in a colander to drain, overnight.  

Next day sieve the tomatoes into a flat dish and cover with double muslin.

Place the dish in the sun for 20-25 days, not forgetting to bring it indoors, during the night.

Then transfer to prepared jars, cover with olive oil, and seal. 

When you open a jar, store it in the refrigerator.