In the morning, she participated in the Macy's Thanksgiving Day Parade. Later, the multi-talented star whipped up a vegan-friendly holiday feast for fiancé Eric Johnson and their families – in her hotel suite, no less.
The newly engaged singer, 30, who just released her new holiday album Happy Christmas, cooked a turkey, but made sure to include some vegan delicacies for her health-minded hubby-to-be.
"She cooked mostly traditional food with some vegan dishes for Eric and his family," says a source close to the couple.
Simpson had to get creative to make Thanksgiving dinner for so many people at her hotel. "They had an oven brought into her suite," says the source. "She also used the hotel kitchen."
Simpson did not make a Tofurkey for her future husband, which she had joked about with Jimmy Fallon last week. "After getting out of the NFL, [Eric] went to this healer and is very healthy," she said. "For Thanksgiving we have to make a Tofurkey!"
And tucking into a vegan meal is a far cry from what Simpson is used to eating, she told Fallon. "I'm from Texas – I'd fry a steak," she laughed. "We eat all casseroles and giblets!"
Also at the Thanksgiving dinner in New York were Simpson's parents, Johnson's parents and some close friends. (Sister Ashlee Simpson-Wentz, her husband Pete Wentz and their son, Bronx, spent Thanksgiving in Los Angeles.)
After dinner, the group headed to Meadowlands Stadium in East Rutherford, N.J., to watch the New York Jets beat the Cincinnati Bengals.
"Jessica and Eric had a great day with their families and a bunch of their friends," says the source.