Italian Style or San Marzano Style Tomatoes. Grown in California “Well duh, Eric I ain’t stupid” is what you’re probably thinking. This commonly available organic supermarket brand uses a similar breed of tomato as the classic San Marzano, but it's grown in California rather than the San Marzano region of Italy. Gusti Blog offers a few tips from the Cosorzio San Marzano for identifying the real deal when buying San Marzano tomatoes. The tomatoes are only sold in cans, either whole or in fillets, so jarred tomatoes or those that are labeled “puree,” “chopped,” “diced,” “sauce,” or “organic” are fraudulent. That it easy enough to spot. There is a brand literally called “San Marzano”. They aren’t. The tomatoes inside these cans may be similar but they aren’t real San Marzano. Brand Value: Every brand of Canned Tomatoes San Marzano has a value all its own. Most brands offer some sort of unique selling proposition that’s supposed to bring something different to the table than their competitors.