Here’s the skinny on what actually flavors a pumpkin spice latte

The arrival of fall means chilly mornings, chunky sweaters, piles of leaves, and of course, Thanksgiving goodness. Yet, somehow, the idealistic image of Autumn feels incomplete without the infamous Pumpkin Spice Latte. Yes friends, it’s October, which means we’re well into PSL season. The coffee drink debuted in 2003—424 million lattes later, it has fully wormed its way into American zeitgeist. Now, it’s hard to imagine Autumn before Pumpkin Spice.

And, according to Starbucks, this year Autumn started on August 27 (the true advent of fall in the northern hemisphere began on September 23), when they officially started selling their warm and frothy seasonal drink in 90 degree weather.

But for all the hype, what actually goes in a Pumpkin Spice Latte is somewhat of an enigma. It’s constituents are surprisingly tricky to nail down. And attempts to pinpoint the exact ingredients in a PSL will lead you on a wild goose chase through the weird underbelly of marketing, secret societies, horticulture, Americana, and emotional branding.

Back in 2003, Starbucks employee Peter Dukes and his team were working on a new project in the company’s ‘Liquid Lab,’ a secure research space in their Seattle headquarters. The team was spitballing about a fancy new coffee drink, meant to capitalize on the change in weather. As the story goes, the team allegedly developed the flavor after drinking coffee and eating pumpkin pie at the same time. Since pumpkin pie’s consistency doesn’t really bode well for mixing into a coffee drink, the team concocted a blend of spices meant to emulate the taste and aroma of the real thing. Once the PSL was born, it took on a life of its own, becoming the first drink to have a verified Twitter account and accumulating an army of unfairly lambasted devotees (some of whom have banded together into the Leaf Rakers Society, a safe secret place to celebrate PSLs and all things Fall).