“Doña MarÃa is “”la mera mera,”” “”la jefa”” and the heart of Tacos Don Ramon, located in San Bernardino, California. The story of Doña MarÃa is one of perseverance. After serving Southern California families for two decades with a modest street cart, Doña MarÃa and her husband, Don Ramon, opened a taqueria of their own in 2017.