How to Make It
Cook pasta according to package instructions. Meanwhile, trim crusts from bread and toast bread. Whirl toast in a food processor just until rough crumbs form. You should have about 1 1/2 cups crumbs.
Heat 2 tbsp. oil in a large frying pan over medium heat. Add chorizo slices and cook until browned on both sides, about 4 minutes. Add garlic and cook until fragrant, about 1 minute. Drain off any liquid and transfer chorizo and garlic to a plate. Wipe any blackened bits out of frying pan with a paper towel.
Add 1 tbsp. oil to pan along with paprika and cook, stirring frequently, about 30 seconds. Add bread crumbs and salt and cook, stirring frequently, until bread crumbs are toasted and paprika is evenly distributed. Transfer crumbs to a plate. Keep pan hot over low heat.
Drain cooked pasta, reserving cooking water, and add to hot frying pan along with 1/2 cup cooking water, remaining 3 tbsp. oil, the chorizo, 2/3 of the bread crumbs and parsley.
Transfer pasta to a serving bowl and top with remaining crumbs, parsley, and pepper to taste.