Using the side of large chef knife smash garlic; discard skins. Halve any large potatoes. Place potatoes in microwave-safe bowl. Cover with vented plastic wrap; microcook on 100 percent power (high) 5 minutes. Stir in garlic. Cover; cook 5 minutes more or until tender, stirring once. Drain.
Meanwhile, heat 1 tablespoon of the olive oil in skillet over medium-high heat. Season steak with salt and pepper. Cook steaks, half at a time, 8 minutes for ribeye or 4 minutes for strip (145 degrees F for medium-rare or 160 degrees F for medium), turning once. Keep steaks warm while cooking remaining steaks.
Add remaining 1 tablespoon oil to skillet. Add potatoes, garlic, and tomatoes. Season with salt and pepper. Cook 5 minutes or until potatoes are golden and tomatoes begin to wilt, stirring occasionally. Serve potato mixture with steak. Top with fresh oregano. Makes 4 servings.