Preheat oven to 220°C. Line an oven tray with baking paper.
Pat chicken dry with paper towels. Place in a bowl, coat in tandoori paste and set aside or marinate (at room temp) while you make the rest of the meal.
For the soup, toss pumpkin, kumara and carrots with honey and half the olive oil in prepared tray. Spread out in a single layer, season well with salt and pepper and roast for 20-25 minutes or until soft.
Meanwhile, finely dice leek and onion. Heat remaining olive oil in a large pot on medium heat. Cook leek and onion, with a good pinch of salt, for about 5 minutes or until soft (if sticking to the bottom of the pan and burning at any time, just stir in 1-2 Tbsp water, and it will unstick). Stir in curry powder, tandoori paste and smoked paprika and continue cooking for a further 1 minute.
Stir in stock, tomatoes, water and coconut milk; bring to a simmer. Add roasted vegetables and continue simmering for a few minutes. Use a stick blender, food processor or blender to puree until smooth, adding a bit more stock or water if you'd like a thinner soup. Season to taste with salt and pepper.
Heat olive oil for chicken in a large (preferably non-stick) fry-pan on medium-high heat. Season chicken with salt and cook for 6-8 minutes until just cooked through and golden on both sides. Set aside to rest for a few minutes before slicing or shredding meat with two forks.
Blend yoghurt, mint and lime/lemon juice until smooth and pale green. Season with salt. Alternatively, just finely chop mint and mix with yoghurt and lemon/lime juice. Thin out with a little water if needed.
To serve, ladle soup into bowls, top with shredded tandoori chicken and drizzle with mint and lime yoghurt. Garnish with coriander, if using.