We often sear cuts of meat in a smoking-hot pan to quickly develop flavorful caramelized crusts. Duck breast, with its hefty layer of fat and lean red meat, requires a different approach. For a perfect magret, we score the breast to encourage rendering, then place it skin side down in a cold skillet before turning on the burner. The slow heat gives the fat time to render, yielding crisp, golden skin and medium-rare meat.