how long to cook tuna steak medium
1 Add the tuna steaks. 2  The steaks should sizzle when added. 3  Cook, uncovered, for 6 to 9 minutes or until fish begins to flake when tested with a fork but is still pink in the center, turning once during cooking. 4  Adjust the heat as needed if the skillet gets too hot.tart with 3/4-inch-thick steaks. 1  Choose a heavy skillet that best fits the number of tuna steaks you are cooking. 2  Add 1 to 3 teaspoons cooking oil or olive oil to lightly coat the skillet. 3  Heat the skillet over medium-high heat until hot. 4  Add the tuna steaks.