Prep Onion and Garlic: Finely chop the onion and garlic. Then, in a large pot with a lid, sauté them in olive oil until the onion is translucent but not browned. Add red pepper flakes if you like a bit of heat.
2 cloves garlic, 1 white onion, Red pepper flakes to taste, 4 tablespoons olive oil
Prepare Stockfish: Rinse the soaked stockfish, remove any skin or bones, and cut it lengthwise in half. Then, chop it into about 0.5-inch thick pieces. Keep the pieces on the larger side to prevent them from breaking down too much during cooking.
1.5 pounds stockfish
Sauté Stockfish: Add the stockfish to the pot and sauté for about 5 minutes, making sure it browns nicely. Then, stir in the tomatoes and add a pinch of salt.
1 cup canned peeled tomatoes or fresh tomatoes, Salt
Simmer: Cover the pot and let the stockfish cook for about 1.5 to 2 hours, stirring gently a few times. If it starts looking dry, add some boiling water. Adjust the seasoning with salt as needed.
Boiling water
Add Potatoes: Finally, mix in the potatoes and cook covered for about 20 minutes, or until they're tender. Add more water if necessary during this time.
2.2 pounds potatoes
Serve the stockfish in a small bowl: This allows the tomato sauce to continue bathing the fish. Enjoy it warm as soon as it's plated or make it rest. Stockfish is often said to taste even better the next day, so don't hesitate to make this dish ahead of time!