Roasted cauliflower with black and white hummus

Ingredients

• 150ml olive oil, plus extra to serve
• 3 curry leaf sprigs (about 30 leaves)
• 570g jar of black (or regular) chickpeas, drained, rinsed and patted dry (400g)
• ½ cauliflower head, cut into bite-size florets (400g)
• 1 large onion, peeled and cut into 8 wedges (200g)
• 4 tsp garam masala
• 1 tsp ground turmeric
• 1½ tsp onion granules
• 1 tsp garlic granules
• ½ tsp caster sugar
• 2 tsp cornflour
• 2 tsp lemon juice
• 200g hummus, shop-bought or homemade
• ¼ tsp chaat masala, to finish (optional)
• Fine sea salt