In a small bowl, whisk together olive oil, balsamic vinegar, soy sauce, black pepper, garlic powder, and onion powder. Place the steaks in a shallow dish or a resealable plastic bag. Pour the marinade over the steaks, ensuring they are well coated. Refrigerate and marinate for at least 2 hours, or overnight for best results. Preheat your grill to medium-high heat.
Remove the steaks from the marinade, letting the excess drip off. Season with salt to taste.
Grill the steaks to your desired doneness, about 4-6 minutes per side for medium-rare, depending on the thickness. Remove from the grill and let rest for 5 minutes.
While the steaks are resting, prepare the honey onions. Heat olive oil in a skillet over medium heat. Add the onions, honey, salt, and pepper. Cook, stirring occasionally, until the onions are caramelized and golden brown, about 15 minutes. Serve the grilled steaks topped with the honey onions.