Peel the pears, remove the core and cut into small pieces. Put together with a cup of water and the juice of half a lemon in a saucepan and cook until soft. Then puree, boil for 4 minutes together with the preserving sugar.
Remove from heat, add the chocolate and fill into prepared glasses as quickly as possible. In any case, so quickly that the chocolate cannot completely dissolve.
Turn the tightly closed jars upside down for 5 minutes.