Preheat the oven to 400°F. Peel and halve the squash, scoop out the seeds and slice into wedges. Trim the cauliflower, cut into florets and place on a baking tray with the squash.
Drain and add the chickpeas, sprinkle over the garam masala and a good pinch of sea salt and black pepper, then drizzle with oil. Jiggle the tray to mix everything together, then roast for 40 to 50 minutes, or until the squash is golden and the cauliflower starts to crisp up.
Pick and add the basil and mint leaves to the processor blender, with half the coriander (stalks and all). Pulse to begin chopping up the herbs. Next, begin peeling the garlic and ginger. Cut the chilis in half and deseed. Then add to the processor with the zest and juice from the lemon and 1 lime. Mix to a paste, gently shaking the processor and scraping down the sides halfway.
Peel and add the banana with a good pinch of salt and pepper, then whiz again, until smooth. Once the veggies are cooked, turn the oven off, but leave the tray of vegetables inside to keep warm.
Drizzle 1 tablespoon of oil into a large pan over a medium heat, add the curry paste and cook for 1 to 2 minutes, then stir in two-thirds of the roasted veggies, popping the rest back in the oven to keep warm.
Pour in the coconut milk and a half cup of water, then let simmer for 15 minutes, adding a splash of water to help loosen, if needed. Season to taste, then scatter over the remaining roasted vegetables and place the remaining coriander leaves on top.
Crumble over a few poppadoms and squeeze the remaining lime on top of the final product - delicious served with fluffy rice.