Heat olive oil in a dutch oven or large saucepan.
Saute onions until translucent, about 10 minutes.
Add minced garlic, saute for a minute or two.
Add wine, scrape pan to deglaze.
Add crushed tomatoes, fish stock, diced tomatoes, salt, pepper, parsley & crushed red pepper.
Bring to a boil. Reduce heat and simmer, covered, for 15- 20 minutes, stirring occasionally.
Taste, add additional red pepper if more heat is preferred.
Add sardines. Stir in, breaking up some sardines.
Simmer for 10 - 15 minutes.
Salt & pepper to taste if necessary.
Serve with lots of crusty bread for dipping.