Heat the oil in a pan over a medium heat. Add the cumin and fennel seeds and cook for 2 minutes until fragrant and sizzling. Then add the onion with a pinch of salt and cook for 7-8 minutes until softened. Add a splash of water if they start to stick. Add the garlic and cook for a further minute until fragrant.
Add the turmeric, curry powder, ginger and tomato puree with a splash of water stir to create a paste. Fry off for 1-2 minutes.
Pour in the carlin peas with their bean stock, coconut milk, stock cube, if using, and the spinach. Stir to combine and simmer for a few minutes until the mixture thickens slightly.
Transfer 2 ladle-fulls of the mixture to a blender or food processor and blitz into a puree. Stir this green puree back into the pan. If it’s looking a little thick, some of the remaining coconut milk or water to loosen. Check for seasoning - keeping in mind the halloumi is salty! - and reduce to a low simmer.
While that’s simmering, add the diced halloumi and mango chutney to a small bowl and toss to coat. Heat a non-stick pan over a medium heat and cook the halloumi until golden all over, turning regularly, about 3-4 minutes . Add a splash of oil or water if it gets a little sticky.
Once the curry has reached a creamy consistency, serve into bowls. Top with some yogurt and scatter over the halloumi chunks. Finish with a sprinkle of nigella seeds, if using. Dunk with warm naans to serve, or with rice for something heartier.
