Heat the oil in a large pot over medium-high heat. Add the garlic, sausages and onions and cook until lightly brown.
Add the crushed San Marzano tomatoes and 1/2 can water, bring to a simmer. Add the tomato puree, 1/2 can of water and simmer again. Repeat with the tomato sauce, again adding 1/2 can of water and bring the sauce to a simmer. Add the tomato paste and cook through.
Add the basil, parsley, marsala wine, pepper, salt and sugar into the pot and stir. Simmer for 2 to 3 hours, stirring frequently.
This recipe was provided by a chef, restaurant or culinary professional. It has not been tested for home use.