Flank Steak and Grilled Veggie Pita

Name: Flank Steak and Grilled Veggie Pita
Ingredients: 2 garlic cloves, smashed and finely chopped; 2 teaspoons coriander, toasted and ground; Pinch cayenne pepper; 1 lime, zested and juiced; Kosher salt; Extra-virgin olive oil; 1 flank steak, trimmed of excess fat; 2 red or yellow bell peppers (or one of each); 1 large zucchini or 2 small, 1/2-inch slices on the bias; 1 large red onion, cut into 1/2-inch rounds; 2 cups washed baby arugula; 1/4 pound shaved Parmigiano; Balsamic vinegar; 4 whole-wheat pita pockets