Manjar de Piña
On a large saucepan, pour 5 cups of the juice and the sugar, cook under low fire until the sugar is completely dissolved.
In a separeted bowl, dissolve the cornstarch with the remaining cup of pineapple juice.
Pour this mixture into the saucepan, slowly to avoid lumps.
Cook, stirring constantly until the mixture start to thicken.
Pour the mixture on a bowl. Let it cool down to room temperature and then refrigerate until set.