Directions

1. Cut steak into 1-inch cubes; place in a shallow dish or resealable plastic bag. Add garlic, lemon juice, 2 tablespoons of the oil, and salt and pepper to taste; toss to coat. Cover dish or seal bag; refrigerate 1 hour.
2. Coat grill rack with nonstick cooking spray. Preheat grill to medium-high (350°F to 400°F). Drizzle tomatoes with remaining 2 tablespoons oil, and season with salt and pepper to taste. Grill tomatoes, cut side down, 1 to 2 minutes or until slightly soft. Set aside; let cool.
3. Thread meat onto 8 skewers.? Grill skewers 5 to 8 minutes for medium-rare, or to desired doneness, turning several times.
4. Place 2 tomato halves on each plate; sprinkle with onion and jalapeño. Place 2 skewers on each plate, drizzle with vinegar, and serve.