Here's a question for you: is there anything out there, and more on the nose anything I've got a chance of finding here in Ecuador, that is an acceptable substitute for Pandan leaves? (I've got access to everything from breadfruits to various jasmines, but Pandan is sadly lacking in this country.) I have a serious hankering for Hainanese Chicken Rice, and every recipe I can find calls for them as a major component of the flavour.
Alternately, will the dish come out tasting proper without them?
The closest i can think of as a substitute for pandan is vanilla, but i have not tried it. I would definitely not recommend the use of bay leaves, tarragon, dried basil, etc as substitutes, i would rather do without, as earlier posters have written.
Frozen panden leaves should work, but you may have to double the amount called for in the recipes. Similarly, i cannot comment on extracts or essences, as i have not used them. However, as previously pointed out, make sure that the extracts/essence is the real thing, ie extract of Pandanus Amaryllifolius (although i am not sure they would go into such detail in their list of ingredients), and with nothing else added in, if possible.
The so-called Thai Pandan rice, or Thai jasmine rice, may be as difficult to get in Ecuador as pandan leaves, but if you can get them (import from Canada? they are readily available in chinese/asian grocery stores there), they could provide some of the aroma of pandan leaves, if you are hankering after the ' authentic' HCR.
For what i think you are after, your ultimate solution would be to grow your own pandan leaves, it should be Pandanus Amaryllifolius. I have seen pandan plants for sale in some nurseries and asian grocery stores in and around TO (obviously in the summer months). I am quite sure you can buy it online either US or Canada, but doubt if they will deliver across their borders. You may want to consider smuggling, or importing a pandan plant and go thru whatever loops and expenses necessary to import plants to Ecuador. I am quite sure they will thrive in any equatorial or tropical climate, and if not, then perhaps as indoor plant?
There are many, many varieties or species of pandanus, just make sure it is Pandanus Amaryllifolius (and not any other pandanus, I know i am repeating myself ad nauseum), and if you are buying the physical plant, ie not thru the internet, then just crush a small sample of the leaf and smell it to confirm its what you want. I think gardenweb has info on buying and growing pandanus amaryllifolius... its been awhile since i last checked into that website. Try online nurseries that sell ' exotic' or tropical plants in canada, i am quite sure they stock them, perhaps at a price premium.
IMO, the reason why there are HCR recipes that do not call for pandan leaves could be because of the personal preference of the author or, much more likely, because the recipes are authored by emigres living in countries where pandan leaves are not available.
I find it hard to believe that pandan leaves would NOT be an ingredient in any ' authentic' HCR recipe. The plant is ubiquitous and grows easily in SE Asia (no matter what you do or do not do to it) and is frequently used in SE Asian cuisines. It is used in ethnic Malay cuisine when rice is flavored, eg in nasi lemak, nasi kuning, nasi minyak, etc. HCR is Chinese-Malay fusion cooking and the recipe for the rice is one feature that distinguishes the rice component from the usual Chinese (which is usually plain boiled rice) or the Malay recipes for rice. In Malay or Nonya desserts, pandan is commonly used, and often paired with coconuts and palm sugar.
Other than the rice and pandan leaves, you may want to also concentrate on what distinguishes HCR from any other poached chicken (Chinese or otherwise). HCR is a chicken-y overload experience. The chicken is poached in chicken stock which is then used to cook the rice. The rice is first fried with rendered chicken fat, with garlic and ginger before being boiled/steamed with the stock and pandan leaves. It is quite common to add rendered chicken fat to the 2 condiments, the chilli/garlic/ginger mixture and the ginger by itself.
And of course, the chicken. It should have an exfoliating scrub with coarse salt, for aesthetic reasons and i believe it denatures the skin such that if you use the multi-dipping method (alternating between hot and cold water) you could get a chicken with skin that is thick and plump with gelatinous collagen.