Apply cooking spray to grill pan and heat over high heat. Cook steak about 3-4 minutes on each side for medium rare or longer to your desired degree of doneness.
While steak is cooking, blanch green beans, and then set aside to cool.
Assemble salad by placing arugula in a large salad bowl; add thinly sliced onion, cooled green beans and cheese.
Plate salad and top with sliced steak. Drizzle with your favorite dressing and enjoy!