A few years ago, I read somewhere that Italians never use onions and garlic in their marinara; it’s always one or the other. Like so many black-and-white cooking “rules” you come across online, this one didn’t stand up to cursory Googling—it might be true in some regions of Italy, but it’s more of an old-school…
Source: LifeHacker – Your Marinara Needs Onions or Garlic, but Not Both