For the mango jam, first dice the peeled and pitted mango. Put all the ingredients in a large enough pot and leave to infuse, covered, for about 2 hours.
Remove the lid. Bring to a boil and cook until bubbly, about 3-5 minutes. Stir constantly and skim.
Make a jelly test. If it gels, pour the mango jam into sterile jars and seal tightly. Place on the lid for a few minutes, then invert and allow to cool completely.