Preheat the oven to 180°C. Halve the tomatoes. Place cut side up, on a lined baking tray with the prosciutto, drizzle with 1 tbsp olive oil and season with pepper. Bake for 15 minutes or until the tomatoes are tender and prosciutto is crisp. Let cool.
Meanwhile, heat a ribbed grill pan or barbeque over a high heat. Lightly brush the asparagus with 1 tbsp olive oil and grill for 1 minute each side. Remove from the heat and set aside.
To make the dressing, shake all ingredients together in a screw top jar until the sugar dissolves.
Arrange the rocket and asparagus on serving plates, top with tomatoes, prosciutto and parmesan. Drizzle with dressing and serve as a light meal or to accompany grilled meat.