Peel skin of squash. Cube. Cook with a little water, turmeric and salt. When done yet firm, add coconut and green chilli mix. Pour seasoning on top. If there's more liquid it becomes kootu, if moist but not liquidy then poduthual.
Variations: Can do plaintanos (raw, green or, if not there, very, very green chiquita bananas) for a vazhakai poduthual/thoran. Also can do red pumpkin/butternut squash similarly.
An excellent and quick ckakka thoran is also possible. A Thai canned product is green jackfruit, already cooked. Just shred this by hand, prepare seasoning in 5-6 tablespoons oil and toss crushed coconut and green chillies in. Salt. Stir well and remove when thoroughly heated through and still moist. This dish needs a fair amount of coconut, and the fresh one is preferred.