Thank you to Bill Avery for contributing this great old image. I loved this Mr. Donut dearly from 1963 through 1965 because I had an early morning Herald route and we folded our newspapers most of that time at the nearby Thom McAn store at W. 49th and 8th Avenue. This Mr. Donut had their own bakery room and the franchise owner or manager would sell us a dozen warm freshly baked donuts for some ridiculously low price like a quarter or something. I only ate two, usually their glazed chocolate cake donuts and my family and the neighbors got the balance of the box. The Palm Springs Mile Publix Supermarket is visible in the background, along with the "Z" in the Zayre store just to the west. Mr. Donut was just to the west of Palm Springs Lanes, a long-time popular bowling center serving most of Hialeah and owned by the Facente family.
The Mister Donut chain of 558 stores was bought by Dunkin Donuts in February 1990. The company was owned by International Multifoods Inc., an American food processing company. Dunkin Donuts had just been sold to Allied-Lyons Company. After US Government approval Mr. Donut operated as a subsidiary of Dunkin Donuts but the franchise owners were offered the opportunity to convert to Dunkin Donut stores if they wished to do so. Mr. Donut, combined with Dunkin Donuts, now had 2,400 outlets in the chain. More information, including the two brothers-in-law who started both donut chains, is located at:
http://www.kzwp.com/lyons/dunkin.htm