Here is my summary on orchid as food.
A word of caution, make sure they were not sprayed with toxic chemicals.
Dendrobiums have been used as a vegetable in Asia.
Jumellea leaves are brewed for tea.
In Mexico the pseudobulbs of Laelia superbiens are macerated, flavored and made into confections and shaped like skulls and other objects for All Saints' Day.
In some parts of Brazil the seedpods of Leptotes bicolor are cured and produce a flovoring similar to vanilla which is used to flavor
ice cream.
The tubers of Australian terrestrial orchids and pseudobulbs of Dendrobium speciosum were once roasted & eaten by various Koori tribes in Australia
Starchy tubers of North Amercian lady's slippers were once eaten.
Chinese are said to use the old dendrobium canes for soup.
In fact here is enough orchid eating going on even today that it has prompted an edible orchid conservation group.
"In the southern Africa region (Tanzania, Zambia and Malawi), the tubers of the orchids have for a long time been used as a source of food. The tubers are traded locally within the three countries, where they are used in the preparation of a meatless source.
Orchid farmers in Singapore have recently began to conduct cooking classes using orchids, introducing stir-fried orchids and orchid sauces. Not only are orchids edible, but also gardeners say that it is a source of fiber and vitamin C. So what does it taste like? Opinions vary; some say it is somewhat sweet, others say it tastes like tannin or raw chives.
People in Hawaii have been making salad dishes, cooking orchids and scallops together or have made sugar coated orchid candies since the 1960s. "
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However, the rattailed Oncidium ceboleta has been reported to be used as a hallucinogen when stronger stuff was not available. So check before using