A 3.75 x 3.75″ ashtray.  Information square is fired on the underside. My mother’s favorite restaurant.  Made their own pies with real meringue, browned on top.  In my 20s, I thought the place was stodgy, but I’d love to have a meal there now.  Food was excellent, waitresses motherly.  And I don’t mean that in any derogatory way.
I think the restaurant began in the early 60s.  In 1953, Jack May was managing both Jack’s Grill in Sullivan Gardens and the Luncheonette at the new Little Store.  Jack and wife Jeanette co-owned Center Street Restaurant and, later, Jack’s Restaurant on Main Street.  There’s a complicated history in all this, but I can’t find a source for it right now.  I’ll update as I learn more.

05/08/2021: Updated time line:

From the late 1940s to 1960, the building at 504 West Center Street was owned by Cardwell and Alberta Hounchell. The original building was a a block building painted white (in the only picture I’ve seen of it) and known at “Center Street Restaurant and Grill”. (When I was a kid, we lived in the apartments at 315 Cherokee Street. In one of the apartments lived a man named “Happy” Hounchell. He was a barber with a shop behind Bingham Furniture on New Street. I wonder if they were related.) (the man and the family, not the furniture store and the barber shop)

An ad in the June 6, 1951, issue of the Kingsport News touts a “completely remodeled” restaurant with pale green walls and gray leatherette upholstery. The current building, though, is shown in the records as having been built in 1952.

In 1979, the restaurant was owned by Gary and Angie Francisco. It closed in August, 1989.