These croquettes are made from bacalhau, the dried-fishstaple of Latin America and Western Europe.
Cover cod with cold water in a large bowl; cover with plastic wrap. Refrigerate 12 hours, changing water twice.
Drain and rinse cod. Transfer to a large saucepan; cover with cold water. Bring to a boil. Reduce heat; simmer 5 minutes. Drain and rinse cod. Wrap in a clean kitchen towel, and roll back and forth until cod is dry and finely shredded. Shake into a small bowl; set aside.
Cover potatoes with cold water in a clean large saucepan; season with salt. Bring to a boil; reduce heat, and simmer until tender, about 15 minutes. Drain potatoes, then mash in saucepan; set aside.
Heat olive oil in a large skillet over medium heat until hot but not smoking. Add onion and garlic; cook, stirring occasionally, until onion is translucent, about 3 minutes. Reduce heat to medium-low; stir in cod. Cook until it looks dry, about 3 minutes. Stir in parsley. Season with salt and pepper. Transfer to a bowl; let cool.
Stir eggs and reserved potatoes into cod mixture, mashing ingredients to combine. Mold about 1 tablespoon mixture into a log (slightly taper ends) about 2 inches long. Repeat with remaining cod mixture. Roll logs in breadcrumbs.
Heat canola oil in a large saucepan over medium-high heat until it registers 360 degrees on a deep-fry thermometer. Line a baking sheet with paper towels. Working in batches to avoid crowding, fry logs, turning occasionally, until just golden brown, about 1 minute. With a slotted spoon, transfer to lined sheet to drain. (Adjust heat between batches as necessary to keep oil at a steady temperature.) If not serving immediately, keep warm in a 275 degree oven up to 30 minutes.