Heat the remaining tablespoon of oil in the same pan or skillet over medium-high heat. Spread the remaining 1/2 cup of panko bread crumbs on a plate.
Working quickly, place a salmon ball at the center of the crumb plate. Gently flatten it into a 3/4-inch-thick cake. Turn it over to evenly coat both sides with the crumbs. Transfer to the hot pan. Repeat until all of the cakes are formed and in the pan; discard any remaining crumbs.
Reduce the heat to medium; cook the cakes for about 4 minutes on the first side, until golden, then turn them over and cook for about 3 minutes, until the second side is lightly browned and the cake is cooked through.
Transfer the cakes to a platter or individual plates to rest for 5 minutes before serving.