Chilacayote (Cucurbita ficifolia) is known as Malabar Gourd, Courge de Siam in French and Chila in Portuguese, belongs to the Cucurbitaceae family which includes the cucumbers, melons, squashes, and pumpkins all of them heat lovers.
One Chila plant is a rampant vine that will take a vast amount of space and climb everywhere. It can be also very prolific, I had 25 large fruit from one plant in the summer of 1999, I must confess that I planted it under the manure heap.
The fruits are extremely decorative and will keep indoors for a long time, however they must not be eaten before toxins are washed away otherwise you might have a bad tummy upset. I have read that bitter marrows and cucumbers can have toxins called 'cucurbitacins' however I have no idea if it is also the case with the Chilas.
Therefore this is a somewhat complicated recipe for a very pretty jam which can be made with its thread like flesh. This jam is very popular in Portugal where Chilas are grown throughout the country and forms the basis for many traditional sweet meats.
The older the Chila the better it will be, so you may keep yours for decoration and when you get tired of it or it has developed some soft spots, then cook it. They can keep for several years and when the green colours start fading then they are ready for the pot.
Start by cracking the Chila, if in doubt throw it on the floor and it will split nicely. You must remove all the spine like dark bits in the centre by hand in order to avoid breaking the threads. Just boil the chunks after peeling and deseeding it. After it has been boiled remove any seeds that were left over then keep the flesh in plenty of cold water with lemon peel for two or three days. Change the water several times a day, I think that the reason for this is to remove the toxins. Drain very well squeezing it by hand and weigh.
Now my 89 years old aunt uses for each kilo 1.3 kg sugar. In a preserving pot dissolve the sugar in a minimum of water and add lemon peel and a stick of cinnamon. Bring to hard ball temperature (120º C/ 250º F) and then add the threads. Cook until it reaches small crack stage (138º C/ 280º F). Pot the usual way.