Heat a large saucepan with the ⅓ cup olive oil over medium heat. Sauté the large chopped onion and when soft, add the sliced cuttlefish and squid, not the tentacles, and cook until lightly golden. Add the 4 cloves garlic and chopped parsley, stirring to combine. Pour in the wine, vinegar and then stir in the ink paste. Cook for a further 5 minutes. Season with salt and pepper, to taste.