The customer left a $1,000 tip on her $63.31 restaurant bill.
The kind customer's identity is a mystery to us all, but it sounds like the restaurant staff knows who she is.
"She said she was just happy that we are still open. Amazing. And WOW," Fentons wrote on Facebook. "WOW" is right.
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"We are filled with gratitude for ALL who have been able to stay in there with us this past year via take-out orders, curbside pickup, deliveries, gift card orders, caramel and chocolate sauce orders shipped to friends, cake Orders, sweet notes of encouragement to us, and more," the restaurant continued.
Fentons Creamery was founded in Oakland in 1894. It's a family favorite for decadent ice cream sundaes on Oakland's Piedmont Avenue.
The restaurant is open for takeout, outdoor dining and indoor dining at 25% capacity.