They look like a throwback to the psychedelic, tie-dyed days of the 1960s. Topped (and bottomed) with a layer of chocolate, each colored layer flavored with almond paste, with thin coats of apricot or raspberry jam in between, who can resist buying a string-tied, neat little white box of these little dolci? For a couple of decades now, even supermarkets, delis and big box stores like BJs and Costco are offering factory-baked versions of them... it's become one of the more popular, year-round cookies in America, but it's especially popular at Christmas because of the holiday colors.
Commenting on the history of the rainbow cookie, "As for the history of the rainbow cookie I believe it’s representative of the Italian Flag and the United Kingdom of Italy as a country instead of independent Provinces. My father would give me a rainbow cookie when I visited as a child in the mid 60’s and all of our family enjoyed eating them as well."
Veniero's makes about 300 lbs of these colored morsels each month, with about 15 cookies in each pound. That number increases around the holidays, Zerilli claims proudly, "So each year, we produce about 3000-3500 lbs!". Veniero’s "Authentic Rainbow Cookie" definitely stands out as one of the best that's enjoyed by folks all over the world.
First of all, it's not really a cookie. It's more of a triple-layer sponge cake, although some bakeries put so much almond paste into their sponge that they really aren't "cake" any more! They are baked in large sheet pans and meticulously cut into those little squares that we all love. I shouldn't say "all" love them, because I have met people who just don't go for almond/marzipan flavors, even if they are presented with a neon, edible rainbow.
That's another thing... it's not really a rainbow, which have seven colors. This delightful pastry creation has only three. And while a rainbow comes from white light being broken up by a prism into colors, this cookie has one white layer to start with.
Finally, most claim this recipe is not Italian. They say that it is an Italian-American creation, created to honor the Italian flag by Italian-American bakers. I doubted this, so I did some research... In fact, you can find version called Pasticcini arcobaleno (little rainbow pastries) in Italy during the Christmas season. Besides, nearly every "Italian-American" recipe owes its existence to a recipe from mainland Italy. Perhaps the recipe has changed a bit, its core is Italian. I really can't imagine such a complex pastry preparation coming out of American bakeries alone without any historic link to the traditional recipes of the past.