Preheat your grill to medium-high heat.
In a bowl, combine the olive oil, Dijon mustard, balsamic vinegar, thyme, and salt and pepper to taste.
2 tbsp. olive oil, 2 tbsp. Dijon Mustard, 1 tbsp. balsamic vinegar, 1 tsp. dried thyme leaves, Sea salt and freshly ground black pepper
Add the beef to the bowl with the marinade, and stir until well-coated.
1 ½ lbs. steak
Thread alternating pieces of meat and vegetables onto skewers.
1 red onion, 1 bell pepper, 1 zucchini, Wood or metal skewers
Season each kabob to taste with sea salt and ground pepper.
Sea salt and freshly ground black pepper
Grill the kabobs on the preheated grill, frequently turning, until nicely browned on all sides, about 15 minutes.