- Heat 1 teaspoon oil in medium skillet over medium high heat. Add onion, bell pepper, and ¼ teaspoon salt and cook, stirring occasionally, until lightly browned, 5–7 minutes.
- Meanwhile, puree feta, garlic, lemon juice, oregano, and 1 teaspoon oil in food processor. Set aside.
- Sprinkle steak with remaining ½ teaspoon salt and black pepper.
- Heat remaining 1 teaspoon oil in large skillet over medium-high heat. Add steak and Worcestershire sauce and cook, stirring frequently, until steak is just pink, 2–3 minutes, or to desired degree of doneness.
- Divide steak evenly among buns and top evenly with onion mixture. Drizzle each sandwich with 2 tablespoons feta sauce.
- Per serving (1 sandwich)
Enjoy this hearty sandwich with a healthy salad of chopped romaine and radicchio tossed with thinly sliced red onion, halved cherry tomatoes, red-wine vinegar, and salt and pepper to taste.