01 - Combine olive oil, soy sauce, lemon juice, minced garlic, oregano, black pepper, and salt in a large bowl and whisk until blended.
02 - Add beef cubes to the marinade, toss to coat evenly, cover, and refrigerate for at least 1 hour or up to 4 hours for enhanced flavor.
03 - Heat grill or grill pan over medium-high heat until ready for cooking.
04 - Thread beef cubes, bell peppers, red onion, zucchini, and cherry tomatoes alternately onto metal or wood skewers soaked in water.
05 - Brush assembled skewers lightly with olive oil and season with salt and pepper to taste.
06 - Cook kebabs on the grill for 10 to 15 minutes, turning every 3 to 4 minutes until the beef reaches desired doneness and vegetables are tender with light charring.
07 - Remove kebabs from grill, let rest for 3 minutes, and serve immediately while hot.