This is one of the most demanding of jams to make; it can be made in several different ways of which the following is the quickest and most simple.
Remove the hulls from strawberries which have just reached the exact stage of ripeness; do not wash them unless absolutely necessary.
Add the fruit, then take the pan off the direct heat but keep it hot for 7–8 minutes until the juice from the strawberries has dissolved the sugar and turned it into a syrup.
Drain the strawberries on to a sieve; cook the liquid rapidly until it begins to reach the setting stage then at this moment, replace the fruit and cook for a further 5 minutes until the required degree.
Fill the jam into warmed jars a little at a time so as to distribute the strawberries evenly throughout and prevent them coming to the surface in a mass; this will happen if the pots are filled too quickly.