For the Veracruz sauce, fry the 1 small onion and 4 large cloves garlic in 2 tablespoons olive oil until soft and translucent. Add the 3 medium tomatoes, 1 Serrano chili, ½ cup pitted green olives, ⅓ cups capers in brine, ½ teaspoon Mexican oregano, ¼ teaspoon marjoram and 1 bay leaf. Cook over medium high heat for about 20 minutes to reduce the amount of liquid and concentrate the flavors. Taste it and add ½ teaspoon kosher salt as needed (about ½ tsp of kosher salt should do it).
2 tablespoons olive oil, 1 small onion, 4 large cloves garlic, 3 medium tomatoes, 1 Serrano chili, ½ cup pitted green olives, ⅓ cups capers in brine, ½ teaspoon Mexican oregano, ¼ teaspoon marjoram, 1 bay leaf, ½ teaspoon kosher salt