In 1958, Mr. Ando — virtually penniless after a credit association he served as chairman went bankrupt — began experimenting with ways to prepare flavored noodles by simply adding hot water.

Image Momofuku Ando in 2005. Credit... Kyodo News, via Associated Press

The idea stemmed from an experience a decade earlier, when Japan was still ravaged by postwar poverty. In “The Story of the Invention of Instant Ramen,” an autobiography published in 2002, Mr. Ando told of walking through the rubble-strewn streets of Osaka.

“I happened to pass this area and saw a line 20, 30 meters long in front of a dimly lit stall from which clouds of steam were steadily rising,” he wrote. “People dressed in shabby clothes shivered in the cold while waiting for their turn. The person who was with me said they were lined up for a bowl of ramen.”

“I realized that people were willing to wait patiently just for a bowl of ramen,” he said.

Ordinary unflavored noodles were not the solution; Mr. Ando insisted that his noodles be tasty, inexpensive and easy to prepare. The problem was flavoring them without making them mushy. Using a secondhand noodle-making machine and a large wok, Mr. Ando sprinkled soup on the noodles with a watering can, then kneaded and loosened them by hand after letting them partly dry. “This allowed the noodles to soak up the soup on the outer layer,” he wrote. “I then dried the noodles so they would keep longer and could be easily prepared with boiling water.”