Slice the cod into cubes and the calamari into rings, and place them in separate bowls. Add the shrimp in a third bowl, and season all 3 with salt and pepper. Set aside.
Step 2
Add the onion, ginger, and garlic to a food processor and pulse until fine. Alternatively, you can finely mince them. Add the oil and butter to a pot and place over medium heat.
Step 3
Add the onion, ginger, and garlic mixture to the pot. Sauté for 3-5 minutes until soft. Add curry powder and tomato paste and cook for 30 seconds.
Step 4
Add the tomato passata and stock and simmer on low heat for 10 minutes. Add the cod pieces and simmer for 10 minutes.
Step 5
Add the calamari and cook for 5 more minutes. Finally, add the shrimp and cook for 2 minutes. Add the lemon juice and take off the heat.
Step 6
Taste and adjust the seasoning to your liking. Garnish with parsley and serve.