Wash the strawberries and let them drain well. Clean the berries and cut into small pieces. Weigh 1 kg of strawberries. Mix with the preserving sugar and citric acid in a large saucepan. Cut the chocolate into small pieces.
Bring the strawberries to the boil over high heat while stirring and let them simmer for about 4 minutes, stirring constantly. Possibly puree the strawberry and fruit mixture. Fold in the chocolate chips.
Pour the hot jam into the prepared jars and close immediately. Place the jars on the lid for about 5 minutes. Turn again and let the jam cool down.