Place 100g (¾ cup) of cashews and 1 cup (250ml) boiling water in a heatproof bowl and allow to soak for 1 hour.
Preheat the oven to 220˚C (200°C fan forced) Place remaining cashews on a baking paper lined tray and toast in oven for 3 minutes, remove and set aside.
Place potato in a saucepan of cold water. Bring to the boil over high heat, then reduce to a simmer and cook for 10 minutes or until just tender. Drain and place in a large roasting pan.
Place cauliflower in a microwave-safe bowl, add 2 tablespoons water and cover with plastic wrap. Microwave on high for 8-10 minutes or until tender. Cool slightly, then cut in to quarters and add to potatoes. Combine 1 ½ tsp of turmeric and cumin with 2 tablespoons of oil. Pour over combined vegetables and gently toss to coat. Season well with salt and pepper. Roast for 30 minutes.
Heat remaining 2 tablespoons of oil in a medium sized saucepan over medium heat. Add onion, celery and garlic to pan and cook stirring occasionally, for 4-5 minutes or until turning brown. Add chilli, coriander stalks and remaining 1 ½ tsp of turmeric and cumin, and stock cook, stirring constantly, until simmering. Drain cashews, add to the sauce then using a stick blender, puree until smooth.
Serve roasted vegetables in cashew sauce. Scatter over coriander leaves and toasted cashews.
Recipe Tip
Other optional sides include rice, flaked coconut and Indian flat breads.