Heat the grill to medium-high heat. Lightly oil the grate.
On a lightly floured surface, roll the dough into 6 (6-inch) rounds. Lay them on flour-covered baking sheets until you’re ready to use them.
Before the pizzas go on the grill, arrange all of your toppings and set them beside the barbecue.
Place the pizza dough rounds on the grill. Depending on the size of your grill, you may have to do this in 2 batches. Close the lid and grill for 2 to 3 minutes, or until there are grill marks on the underside of each round.
Flip the rounds. As the start to puff up, press down lightly with the back of a metal spatula to release some of the air. Quickly divide the bbq sauce, chicken, corn, onion and mozzarella between the pizzas.
Close the lid and grill until the cheese melts, about 3 more minutes.
Remove from the grill, top each pizza with 4 slices of avocado, cut and serve.