1949:  Ex-GI Joe Gregor volunteer firefighter and baker, had a problem, he couldn't please his Avon Park customers who wanted their rolls piping hot!

So Joe, tired of losing customers, tried to find a solution by experimenting with different kinds of dough and methods of baking.

Months went by with no luck.  Then one day he mixed a batch of dough, shaped it into Parker House rolls and put them in a proofing box until they rose.  He lit the ancient gas oven a little later than usual and it failed to preheat properly.  Discouraged and weary Joe slammed the oven door.

Suddenly, the town's fire siren wailed two short blasts.  Joe tore off his apron, ran for the door and then remembered the rolls.

Wheeling around, he turned off the burners, opened the oven door pulled out the tray and...:My gosh," she shouted "This is what I've been looking for!"

What happened was the fire siren had interrupted the baking cycle at the right moment: Brown 'N Serve rolls were born!  

He put them back in the oven and they browned in seven minutes, emerging yeasty-fresh and delicious.  They kept a week even without refrigeration. When word got out, customers flocked to his door. Grocery stores, hotels and restaurants all wanted more then he could make.  

The General Mills Corporation heard about the rolls. The upshot:  Joe accepted their offer of $25,000 for the roll-making process.  And that was the end of Joe’s bakery career.

"General Mills also developed Brown ‘n Serve rolls – a revolutionary technological development in the grocery world. The idea came to Joseph Gregor, a Florida fireman, in 1949.  Gregor had rolls in the oven when the fire alarm sounded, so he turned off the oven. Upon returning, he noticed that the half-baked rolls had kept their shape, so he continued baking them. Thus par-baked rolls and biscuits were born. Gregor, a bakery owner, tested the rolls on his customers with great success. A General Mills salesman
brought the idea to the company’s bakeries research laboratories, which perfected the baking process, and obtained a patent. The patent was then given to the entire baking industry. “What is good for the baking industry is also good for the milling industry,” said Leslie Perrin, then president of General Mills."

http://www.generalmills.com/corporate/company/GeneralMills_History_I_I.pdf