Preheat oven to 180 °C. If you are using sweet potato, wash well and chop into 1” cubes with skin on. Steam for 5-6 minutes.
If you are using purple yam (kand), wash, remove skin, cut into pieces and steam for 5-6 minutes. Add the coconut milk to sweet potatoes or purple yam and bake until golden.
Add the rest of the ingredients to the steamed tubers and mix well. Adjust taste by adding more spice and tamarind paste or lemon juice. Garnish with mint leaves and serve.