Cook the orecchiette in a large saucepan of lightly salted boiling water according to the pack instructions.
Meanwhile, place most of the walnuts, the garlic, oil, cream and grated Parmesan in a small blender and whizz until smooth. Season to taste.
Drain the pasta, reserving a little of the cooking water, then stir through the walnut sauce, adding a little cooking water if needed. Toss in the rocket leaves and transfer to serving bowls. Top with the reserved walnuts and serve immediately.