Combine the grated mango, sugar, and salt in a large bowl. Cover and leave it to rest for 20 to 30 minutes, until the mango has released a significant amount of liquid.

Transfer the mango and all its liquid to a nonstick saucepan and stir in the red chili, cardamom, cumin, fennel, cinnamon, and cloves.

Heat the mixture over medium-high until it just begins to simmer, then reduce the heat to maintain a steady, gentle bubble.

Simmer gently for about 10 minutes, stirring frequently, until the mixture has thickened into a syrupy conserve. It will firm up further as it cools, so avoid over-reducing; if it becomes too thick or begins to crystallize, stir in a splash of water and reheat for a minute or two.

Remove from the heat and transfer the preserve to a glass jar. Let it cool completely to allow the texture to set before serving.