Heat half the olive oil in a heavy based frying pan until it’s very hot. Season the steaks with a light sprinkling of sea salt and black pepper. Lay the fish in the pan and fry for 1-2 minutes, then add the garlic. Keep frying until the garlic is golden brown.
With the garlic still in the pan, turn the fish after 3-4 minutes and cook for 3 minutes on the other side. Make sure the garlic doesn't burn. Remove the fish from the pan to a serving plate.
With the pan off the heat, add the remaining olive oil and a pinch of sea salt to the garlic and juices left in the pan. The residual heat of the pan will be sufficient to warm it all through so there’s no need to put it back on the heat. Add the lemon juice, then the parsley, and give it all a good stir.
Spoon the garlic and juices from the pan over the top of the hake and serve.