The actress, 28, shared a snap of her plate when a follower asked her about the gala's food.
"Give us all the teaaaa! What's on the menu?" one fan tweeted at Palmer. In response, the star shared an image on her Instagram Story of what appeared to be a half-eaten meal consisting of vegetables and grains. Palmer captioned the photo, "This why they don't show y'all the food," before adding, "I'm just playinnnn."
She later shared a screenshot of the photo on Twitter, where she wrote, "The menu chile."
After Palmer's photo went viral online, Bon Appetit advisor Marcus Samuelsson, who helped craft the menu, confirmed to TMZ that her photo did in fact represent what guests dined on at the event. Palmer's dish featured barley topped with roasted mushrooms, plus a tomato salad with corn and zucchini slices.
This year marked the first time ever that the gala's menu was totally plant-based. According to a press release, Samuelsson brought in 10 New York-based chefs to create a menu around the party's theme, "In America: A Lexicon of Fashion."
Fariyal Abdullahi, Nasim Alikhani, Emma Bengtsson, Lazarus Lynch, Junghyun Park, Erik Ramirez, Thomas Raquel, Sophia Roe, Simone Tong and Fabian von Hauske were the chefs selected.
Fashion's biggest night featured hors d'oeuvres like collard greens with hot chow served on coconut buttermilk cornbread, black rice porcini arancini with pumpkin Calabrian chili sauce, and watermelon tart with smoked yuzu soy on a panipuri cracker.
The seated portion of the meal began with a salad featuring farm-to-table ingredients, followed by the creamy barley with corn, pickled turnips, and roasted maitake, and later, apple mousse and apple confit with a calvados glaze.
The Met Gala went plant-based because "we thought it was important to really talk about what's present, what's happening — how food is changing in America," Samuelsson told Bon Appetit in August.
He added, "We want to be the future of American food, of plant-based food. That conversation is happening now."