Ingredient info: Smoked Spanish chorizo is available at Spanish markets, specialty foods stores, and online sources.
Directions
Heat oven to 425°F. Pulse bread in a food processor until coarse crumbs form. Heat 2 tablespoons oil in a large ovenproof skillet over medium-high heat. Add breadcrumbs. Cook, stirring often, until golden and crisp, about 3 minutes; season with salt and pepper. Transfer mixture to a bowl, add parsley and oregano; toss to combine. Wipe out skillet.
Heat 1 tablespoon oil in same skillet over medium-high heat. Add shallot and chorizo and cook, stirring often, until chorizo is just crisp, about 2 minutes. Transfer to a bowl and mix in vinegar; season with salt and pepper. Wipe out skillet.
Heat remaining 1 tablespoon oil in same skillet over medium-high heat. Season cod with salt and pepper and cook until bottom side begins to turn opaque, about 3 minutes. Transfer skillet to oven and roast until fish is cooked through, about 5 minutes longer.
Serve cod topped with chorizo mixture and toasted breadcrumbs.
DO AHEAD: Breadcrumbs can be made 8 hours ahead. Store airtight at room temperature. Toss with herbs just before serving.