The restaurant was originally founded by Giorgi Valastro, an Italian-Sierran restauranteur in the city of Santa Fe Springs, Gold Coast. The name is roughly translated into "Sofia's Treasure" or "The Treasure of Sofia", given so in honor of the Valastro's mother, who briefly manned the restaurant's kitchen as head chef. After opening a second restaurant in the nearby town of Gardena, Valastro seeking to expand his business further, spun off the properties and sold the franchising rights to restaurants to business executive Martin Del Toro, owner of the Del Toro Restaurants group. As a wholly owned subsidiary, the corporate-owned Il Tesoro di Sofia rapidly expanded, adding over 75 franchises across Sierra by 1990.