The night before you want to make the jam, clean the strawberries with a damp paper towel and remove the stems. You can leave them whole if they are small, otherwise cut them into 2 or 4 depending on the size of the berry. Make sure that the berries are completely dry before you do anything.
Take the berries in a non reactive bowl, glass being an excellent choice. Add sugar, cover and let sit overnight.
In the morning, transfer the berries and their juices to a large heavy bottomed pan. Add the juice of 1 lemon, mix well (preferably with a wooden spoon) and heat the mixture on medium-low flame with occasional stirring. Sugar will slowly dissolve and the berries will start to fall apart. The mixture needs to be cooked till it reaches jam consistency*.
Cool the jam completely and transfer into sterilized bottle**. Will store in a cool dry place for almost a year.
* How do you know you reached the right consistency? Book has 2 suggestions, none of which worked for me. First one is to check the temperature of the mixture with a sugar thermometer and when it reads 212ºF it is ready (I don’t own a sugar thermometer and have no intentions of buying one). Second method is to chill a saucer, put a drop of the berry mixture on it, and chill it again for 3 minute. When you try to push the drop it should from ripples (ahhhh.. what?? I didn’t know if chilling should be done in the freezer or in the refrigerator).
So that’s when I had to make an urgent call to my mom, who has jam making experience and she gave me a better idea (that really worked for me). Put a drop of the mixture on a small plate and try to move it around. If it starts flowing then the jam is not ready yet. If it resists movement and doesn’t move, then it is ready; remove from heat immediately. It took about 30-35 minutes for the jam to come together.
**To sterilize jars: Wash in hot soapy water, then rinse thoroughly and drain. Place the jars on a baking sheet and dry in a warm oven for 15-20 minutes.