Cut the salt cod into manageable pieces and place them in a saucepan. Cover with water and bring to a gentle simmer. Add a small pinch of salt, a slice or two of lemon and a bay leaf. Continue to simmer for 20 minutes, until tender but not yet falling apart. When done, transfer the pieces of salt cod to a large bowl with a slotted spoon.

Start to break up the salt cod pieces with a sturdy wooden spoon. When the fish has broken up into shreds, add the garlic (if using) and then start to drizzle the oil into the fish. Stir with the wooden spoon, incorporating the oil slowly into the fish as you stir, as if you were making mayonnaise. Continue like this until the fish has formed a nice, but not entirely smooth paste. There should still be small bits of fish here and there. If you find the paste a bit too thick, you can add a spoonful or two of the cooking water. Taste and adjust for seasoning—you may not need any salt, but you probably will, as salt cod can be surprisingly bland after it has soaked. Mix in some chopped parsley.

Baccalà mantecato should be served at room temperature, typically on top of crostini di polenta as shown in the picture above. In Venice, polenta blanca or white polenta is the most authentic choice, but yellow polenta as shown will certainly do fine if you, like me, you don't have any of the white variety on hand. It can also be served with soft, hot polenta for a more substantial dish.