Peel and chop onions, garlic and ginger, sauté in oil in a saucepan, then add the curry. Add the peeled and diced pumpkin, pour in the broth and coconut milk. Add the lime leaves and chili paste. Simmer until the pumpkin is tender, then remove the lime leaves. Puree and season with the soy sauce.
I really like pumpkin seed oil and add a few drops to the soup when it`s in the plate. If you don`t like it together with the curry etc., just leave it out.
The amount of chilli depends on the desired spiciness, as well as the choice of curry powder. If you can`t find lime leaves, you can also use lemongrass. I buy lime leaves in a large bag in an Asian store and freeze them, then you can take them out frozen and (similar to bay leaves) simply cook them with them.