In a small bowl, combine Herbes de Provence olive oil, Garlic Olive oil, cracked peppercorns and 2 tablespoons Pomegranate balsamic.
Place flank steak in large zip-lock plastic bag and pour marinade over. Seal the bag, pressing out as much air as possible. Marinate in refrigerator for 2 hours or overnight.
When ready to cook, bring the steak to room temperature. Heat grill or grill pan to medium high. Remove steak from marinade and season with salt & pepper. Place steak on grill and brush with 1½ Tbsp Pomegranate balsamic. Cook for 3 minutes. Turn steak over and brush top side with 1½ Tbsp Pomegranate balsamic. Cook for 3 minutes longer.
Remove steak to carving board and let rest for 3-4 minutes. Slice steak on the bias (against the grain) into thin slices. Arrange the steak slices on a serving platter. Pour any juices from carving board over the steak.