To prepare the pesto: Rinse the basil and rocket leaves. Pat dry and blend them in a food processor with 4 tablespoons extra virgin olive oil, 1/2 garlic clove, pine nuts and grated Parmigiano cheese. Season with a pinch of salt and set aside.
Slice the prawns in half; cook for a few minutes in a non-stick pan with a drizzle of olive oil and a sprig of thyme.
Boil tagliatelle in plenty of boiling, salted water. We recommend using 1 litre of water for every 100g of pasta. Before draining, remember to set aside a spoonful of the pasta cooking water to use for combining the pasta and sauce together.
Toss and stir the tagliatelle in a bowl; add pesto, prawns and a spoonful of cooking water to combine. Season to taste and serve.