Heat the oil in a large non-stick pan over a medium heat. Add the asafoetida, bay leaf, panch phoran and chillies and fry for 1-2 minutes, stirring well to combine.
Add the onion, stir to coat in the spices, and fry for 2-3 minutes, or until softened and golden-brown.
Add the ground turmeric, cumin and coriander, the salt, sugar and ginger paste and stir well. Add a splash of water, stir and cook for a further 1-2 minutes.
Add the butternut squash pieces and the boiling water. Bring the mixture to the boil, then reduce the heat to a simmer, cover the pan with a lid and simmer for 10-15 minutes, or until the butternut squash is tender.
Add the chickpeas, ground garam masala and fennel seeds and another splash of water if necessary to keep the mixture loose. Add the salt and sugar, if using. Stir well and continue to cook for 1-2 minutes, or until warmed through. Serve immediately.