Heat the oil in a wide, heavy-based pan over a medium-high heat, add the whole spices and fry until aromatic.
Turn down the heat to medium-low, add the onion and cook, stirring regularly, until soft and starting to brown.
Stir in the garlic, ginger and chopped chilli, fry, stirring, for a couple of minutes, then add the ground spices and fry for another minute.
Turn the heat back up to medium-high, stir in the yoghurt and cook for two to three minutes, until it begins to separate.
Stir in the lamb, salt and whole slit chilli, turn down the heat a bit and cook until the mince begins to release its juices.
Sprinkle the flour over the top and stir in, turn the heat right down and leave to cook for 20 minutes.
Stir in the chopped herbs and peas, simmer for another 15 minutes, then serve as above.
