Season the steak with salt and freshly ground black pepper.
Grill or pan-sear the steak over medium-high heat for 3–5 minutes per side, or until it reaches your preferred level of doneness.
Let the steak rest for 5 minutes, then slice it thinly against the grain.
Prepare the couscous according to the package instructions and fluff it with a fork.
Divide the couscous between serving bowls and top with the cherry tomatoes, cucumber, and crumbled feta cheese.
Arrange the sliced steak over the vegetables.
Whisk together the olive oil and fresh lemon juice, drizzle over the bowl, and serve immediately.