Spinach, Basil and Ricotta Rotolo (Pasta Roulade)

Heat oil and sauté prosciutto and spring onions for 1-2 minutes. Add spinach leaves, cook until wilted, cool and chop finely. Combine spinach mixture, ricotta, basil and egg and season. Place two lasagne sheets next to each other on a piece of muslin, with long edges overlapping by 5cm to form a large rectangle. Brush with milk and spread with quarter the ricotta mixture, leaving a border along the far edge. Using the muslin, roll up the lasagne to form a roll, enclosing the filling and wrapping the muslin firmly around the roulade. Tie the ends securely with kitchen string. Repeat with remaining lasagne and filling to form four roulades. Boil roulades in a deep pan of boiling salted water for 25-30 minutes. Remove, unwrap, cut into slices and serve on a pool of warm tomato sauce, garnished with a drizzle of olive oil, pine nuts and reserved basil leaves. Serve with parmesan cheese.