To make the rocket pesto, place the basil, rocket, pecorino or parmesan, pine nuts and garlic in a food processor and process until finely chopped. With the motor running, gradually add the oil in a thin, steady stream until well combined. Season.
Combine the tomato, bocconcini and onion in a medium bowl. Add 2 tbs of the rocket pesto and gently toss to combine. Season.
Heat a barbecue grill or chargrill on high. Spray the asparagus with olive oil spray and season. Cook on the grill, turning occasionally, for 2-3 mins or until the asparagus is just tender and cooked through.
Arrange the asparagus on a serving platter. Spoon over the tomato mixture. Drizzle with the remaining rocket pesto and sprinkle with basil leaves to serve.
