After convincing his Father, they bought their first corn mill in 1948 for 75,000.00 pesos (the peso-dollar exchange rate fluctuated between $4.85 and $6.95), and took it to Cerralvo, where he started what is now Maseca, the company that manufactures and markets one out of every four corn tortillas in Europe, Asia and Central America. For starting it off they had to sell all of their other businesses, and when they ran out of money, a friend he had made in Cerralvo, General Bonifacio Salinas Leal, governor of Nuevo León, lent them money and kept some of the company's stock that, years later, would sell back to them again. Thus began a long relationship with politicians, which is one of the most repeated criticism that is made to Gonzalez Barrera: leveraging his political connections for his company's growth.

His son Roberto González Sr. was a racecar driver, finishng third at the 1976 12 Hours of Sebring. His grandsons Ricardo González Valdez and Roberto González Valdez are also racecar drivers.

He entered the Billionaire's club not with the tortilla Business, however, but through the Banorte financial group of which, since 1992 he has been the main shareholder, and the only Mexican bank to remains in Mexican ownership after the economic crisis of 1995. Its equity stake in Banorte, the third largest bank in Mexico, returned Gonzalez Barrera to 2011's Forbes list of billionaires, and that fact changed the nature of his wealth.

Some health and family problems threaten Maseca (where 23% of the stock is owned by U.S. conglomerate Archer Daniels Midland). and most of the remainder is split in half, with 50% held by his first wife, from whom he never divorced. González Barrera died in Houston, Texas, on 25 August 2012 from complications of cancer, he was 81 years old.