1. Select good, fully ripe mangoes and extract the pulp. Strain the pulp to remove the fibres. If the pulp is not very soft, add some water to the mango pieces and boil to softness.
2. Add the sugar and citric acid to the pulp and cook on a low fire stirring all the while until it reaches jam consistency. Test for setting.
3. When set, remove from fire, add the lime juice, colour and essence, and while still hot pour into a sterilised jar.