In a small bowl, whisk together olive oil and garlic; allow mixture to sit at room temperature while you prepare the couscous.

In a medium saucepan with a tight-fitting lid, boil the water over high heat. Add the couscous then turn off the heat, cover and allow it to stand for 5 minutes. In a large bowl, place couscous, olives, lemon zest, lemon juice, parsley, salt and pepper.

Remove the garlic from the olive oil and discard it. Add the olive oil to the couscous mixture; stir to combine then heat in a medium skillet over medium heat. Add steak; sear for 5 minutes per side then thinly slice and serve with couscous.