What they have in common is what what most people have come to identify as the flavor are really the cheaper, sometimes synthetic, substitutes rather than the original thing. Some may still be shocked to learn that the little green pat of fiery paste in most sushi restaurants isn't wasabi at all, but a mixture of horseradish, mustard, and green food coloring. The real thing may disappoint hardcore wasabi heads raised on the common stuff, because it's expensive, and so labile (it must be grated and used table side due to the volatile nature). True wasabi doesn't preserve well.
Likewise, true vanilla is pretty expensive and heat sensitive as well, so artificial vanilla is likely what most people associate with vanilla flavor. Encountering the variable and heady aromas of true vanilla beans can be an eye opener for novices, but they'd be disappointed to learn that it is destroyed so easily by heat. Thus, for cooking, artificial vanilla is actually preferable. And it's more reliable.
Pandan is less familiar to American or European readers, but it's wildly popular in Asia. The pandanus plant conveys an ethereal floral fragrance that complements coconut and rice powerfully, but is also used in a huge number of applications in numerous countries and cultures. Most often, though, it's associated with green sweet food.
|Pandan kaya bread, Singapore
|Cendol - a pandan flavored starch noodle served on ice with gula melaka, Kuala Lumpur, Malaysia
My most recent attempt tries to intensify the pandan flavor by keeping it in striations in the bread rather than diluted out throughout the bread matrix. To do this, I mixed the pandan extract with some glutinous rice flour (mochiko) which is then folded into the bread. The mochi layers are then cooked inside the loaf by steam. The result is a contrast of crunchy and chewy with hits of pandan flavor. Plus I preserve more of the green color (this time, this is chlorophyll).
Then again, pandan works really well in delicate savory applications:
|Black drum, wrapped in pandan leaf, and grilled. Chef Steve Marques, BRC Gastropub, Houston, TX.