Francis, 15, stopped by the late-night talk show on Tuesday, March 21, with one goal in mind: selling her 101,106th box of cookies. She explained to Fallon, 42, that she reached the impressive number of sales by setting up a stand in front of local grocery stores and singing and dancing for her customers.
"I made up cookie tunes," the seven-year Girl Scout explained. "I took popular songs and changed around the words a little bit. One of my favorites was to the tune of 'Rudolph the Red-Nosed Reindeer.' I changed the words a little bit to list off all the cookies."
Francis then belted a snippet of her rendition of the holiday classic. "You know Samoas, Tagalongs and Do-si-dos. Trefoils, Savannah Smiles, Toffee-tastic. But do you recall the most famous cookie of all? Thin Mints, the most fabulous," she sang as the audience cheered.
To sell the record-breaking box, the teen brought five varieties of cookies for Fallon to choose from. He immediately eliminated the newest flavor, S'mores, and the shortbread Trefoils, the latter of which he called "too basic." He also said goodbye to Tagalongs, revealing that he doesn't like peanut butter.
Ultimately, the TV personality decided to purchase a box of Samoas. After joking about the $4 price tag, he handed Francis a $5 bill. She charmingly said, "Thank you so much for your support."
Fallon quipped, "You're saying that before you gave me the dollar. You're really good at this." He let Francis keep the change and surprised her with a $15,000 check made out to the Girl Scouts of the USA.
The Tonight Show Starring Jimmy Fallon airs on NBC weeknights at 11:35 p.m. ET.
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