The 21-year-old singer and the 'Twilight Saga' actress - who have been dating Joe since last summer - took time out from their late night meal at the Ichiban Japanese Grill and Sushi Bar in Baton Rouge to chat to and pose for pictures with fellow diners and staff.
One of the managers told People magazine: "They were really friendly. They just walked in, sat down, and the word started going around that they were here.
"They each had a Hibachi meal and some sushi. The kitchen crew and wait staff were excited to see them. Some of them stayed late because they were hoping to get their picture.
"I don't watch the 'Twilight' movies, so I wasn't so familiar with them. But everyone else in the restaurant knew who they were. They were definitely there together, as a couple. I have to say, they were very nice. I think they'll come back."
Ashley, 23, is currently filming 'Breaking Dawn' the two-part finale to the 'Twilight: Saga' series in Baton Rouge and is expected to remain in the city for two more weeks.