Heat the olive oil in a large pot over medium heat. Add the sliced onion and minced garlic. Cook for 3 minutes until the onion softens.
Stir in the sliced bell peppers and potato rounds. Cook for 2 minutes, stirring once.
Pour in the diced tomatoes with their juice, then add the saffron threads, white wine, and bay leaves. Bring the mixture to a gentle simmer.
Cover the pot and cook for 15 minutes until the potatoes are almost tender.
Lay the fish chunks on top of the vegetables. Cover again and simmer for 6 to 8 minutes until the fish flakes easily.
Remove the bay leaves. Season with salt and black pepper to taste, then sprinkle with chopped parsley before serving.