Mix all the ingredients for the marinade together in a large bowl and gently fold the grouse breasts into it. Leave to marinate for 30 minutes.
Heat the oil in a pan, add the fenugreek seeds and dried red chillies and let them pop. Add the pumpkin and stir over a high heat for 3–4 minutes. Stir in the salt, chilli powder and turmeric, then reduce the heat, cover and cook until the pumpkin is soft and begins to break down. Stir in the sugar – the sweetness balances the heat and spice and also makes the chutney glossy. Finish with the dried mango powder or mango pickle.
For the mince, heat oil in a pan, add the pickling spice mix and when it crackles, add the garlic followed by the onions and cook till golden brown, add the turmeric and chilli powder followed by the grouse mince and cook until the mixture is nearly dry.
Add salt, diced tomatoes and coriander leaves and mix well. Check for seasoning and you might want to add a touch of sweetness by adding jaggery or sugar to balance the flavours.
To cook the grouse, heat the oil in a frying pan, add the marinated grouse breasts and sear for 30 seconds on each side. Place the pan hot oven and cook for 5 minutes. Remove from the heat, sprinkle with green coriander and leave to rest for 5 minutes, and then serve with the pumpkin chutney and grouse mince.
Tip: Take care not to over cook the breasts, as they dry up very quickly. Since it is a very lean meat, grouse is best cooked fast and served medium. Cooking it on the bone also prevents it getting dry.