6 boneless skinless chicken thighs (1 1/2 lb/675 g total)
1/2 tsp each salt and pepper
1 ball (700 g) prepared pizza dough
1 cup (250 mL) grape tomatoes, halved
1 lb cocktail bocconcini, halved
1/4 cup pesto
1 cup baby arugula
Whisk together 1/4 cup (60 mL) oil, balsamic vinegar, honey and garlic; pour into large re-sealable bag. Add chicken; seal bag, releasing as much air as possible, and massage chicken to coat evenly. Refrigerate for at least 4 hours or up to overnight.
Preheat grill to medium-high heat; grease grates well. Sprinkle chicken with salt and pepper. Grill chicken, flipping once, for 10 to 12 minutes or until well marked and cooked through. Let stand for 5 minutes; slice thinly.
Divide pizza dough into 4 portions. On lightly floured surface, roll out each portion into thin 8-inch (20 cm) round. Brush some of the remaining oil over one side.
Place rounds on grill, greased side down. Grill for 2 to 3 minutes or until lightly browned and set on bottom. Brush tops with remaining oil; flip over and reduce heat to medium. Working quickly, divide chicken, tomatoes, bocconcini and pesto among pizzas.
Cover and grill for 5 to 7 minutes or until dough is cooked through and toppings are warmed. Remove from grill; top each pizza with arugula before serving.