Preheat the oven to 200°C fan. Scatter the cherry tomatoes on a baking tray and spray with low-calorie cooking spray. Season with salt and freshly ground black pepper, and roast for around 15 minutes.
While the tomatoes roast, cook the pasta according to packet instructions (usually around 10-12 minutes in a pan of boiling water). When cooked, drain and rinse under cold running water to cool quickly. Drain thoroughly.
Make the dressing by placing all the ingredients, except the water and salt and pepper into a blender or mini chopper. Blitz to a smooth dressing. Use a little water to thin down if needed. It should be the consistency of thick cream. Season to taste with salt and pepper.
Place the drained pasta, cherry tomatoes, mozzarella, pine nuts and rocket in a mixing bowl. Add the dressing and gently toss together until well combined. Serve.