Cut steak into 3/4-inch cubes and season with salt and pepper.
Heat half of the oil in a large heavy bottom skillet over medium high heat. Add half the steak in a single layer and cook, turning a few times until golden and medium rare, about 5 minutes, or to your liking.
Add 2 tablespoons butter and half the garlic and toss to coat.
Remove steak to a serving bowl.
Repeat with remaining steak, remaining 2 tablespoons butter and half the garlic.
Toss steak with the butter and garlic from skillet.