Katsudon Panggang (Mangkuk Nasi Potongan Panggang Renyah Jepang)

Bahan-bahan (2 porsi)

• 1 cup panko (Japanese breadcrumbs)
• 1 Tbsp neutral oil
• 2 pieces boneless pork loin chops (½-inch thick)
• 1 tsp Diamond Crystal kosher salt
• freshly ground black pepper
• 1 Tbsp all-purpose flour (plain flour) ((or more, if needed))
• 1 large egg (50 g w/o shell)
• ½ onion ((divided; ¼ onion per serving))
• 2 large eggs (50 g w/o shell)
• 2 servings cooked Japanese short-grain rice ((typically 1⅔ cups (250 g) per donburi serving))
• 1 cup dashi (Japanese soup stock)
• 2 Tbsp sake
• 2 Tbsp mirin
• 2 Tbsp soy sauce
• 2 tsp sugar
• 4 sprigs mitsuba (Japanese parsley) ((optional; or use chopped green onion/scallion))
• shichimi togarashi (Japanese seven spice) ((optional))