Lightly beat 3 large eggs in a medium bowl. Place 2/3 cup all-purpose flour and breadcrumbs in 2 separate wide, shallow dishes. Season eggs, flour, and chicken with coarse salt and freshly ground black pepper. Working with 1 cutlet at a time, dip into flour, turning to coat and shaking off excess. Dip into egg, and lift out, letting excess drip off. Dip into breadcrumbs, pressing firmly to help them adhere. Transfer to a plate or pan, and refrigerate at least 30 minutes and up to 2 hours. If needed, separate layers with wax paper or parchment paper.