Wash the rocket leaves and set them aside.
Peel the butternut squash. Cut in half, remove the seeds, cut each side in half, and slice evenly.
Peel the mango, remove the seed, and cut it into batons.
Finely chop the ginger.
Heat the oil in a pot over medium heat. Add the asafoetida and black mustard seeds. Once the seeds pop, add the yellow mustard powder, turmeric and green chilli.
Add the chopped ginger and fry for a minute, then add raw mango and sauté for another minute
Add the sliced squash, season with salt, and add the water. Cover and bring to boil. Once it comes to a boil, turn the heat down and simmer until the squash has cooked.
Add the rocket leaves once the squash is tender and stir to mix. Cook for two minutes and then take off the heat.
Serve hot with steamed rice or flatbread