Wash the strawberries under running water and drain them.
Chop the fruits.
Transfer the strawberries to a large, heavy-bottomed saucepan and add the sugar.
Bring to a boil and continue cooking over low heat for 30 minutes, stirring regularly.
Prepare the jars: boil the jam jars and lids to sterilize them, let them dry before filling.
Pour in the essential oil and transfer the jam to the jars, close and turn upside down. Wait until it’s cool to turn the jars back.
Keeps in the refrigerator for 2 to 4 weeks.