Place beef, spice, tomatoes, chickpeas, prunes and onion in a large cast iron casserole or saucepan with heavy base. Cut pomegranate in half and tap seeds into a bowl. Reserve half of the seeds for serving and squeeze remaining seeds into the bowl to collect the juice. Pour juice through a sieve into the casserole discarding the squeezed seeds.
Add 250ml water and bring to a boil. Cover with lid, reduce heat to low and simmer for 30 minutes, stirring once to ensure it is not sticking. Add pumpkin and cook for 15-20 minutes or until pumpkin is just tender. Simmer uncovered for 5-10 minutes if sauce needs thickening. Add kale and stir through. Add a squeeze of lemon juice and check seasoning.
Cook cous cous according to packet directions.
Place tagine mixture in serving dish and scatter with chopped pistachios and pomegranate seeds, dollops of yoghurt, coriander and lemon wedges. Serve with cous cous.
Tips
Trim any large pieces of fat or sinew off before cooking
You can make this with chuck steak, but will need to cook it for longer until it's tender before adding the pumpkin, about 1hr 30 minutes.
