A New Year feast at Petersham Nurseries: lasagne with spinach and buffalo mozzarella For the lasagne: 1.5kg (3lb 5oz) spinach leaves, washed thoroughly 500g (1lb 2oz) ricotta 750g (1lb 10oz) buffalo mozzarella extra-virgin olive oil, for drizzling 1 tbsp fresh marjoram or oregano leaves, chopped (optional) 150g (5½oz) lasagne sheets approximately 80g (3oz) freshly grated parmesan Put the butter in a heavy-bottomed pan over a low to medium heat. Add the flour and stir together for a few minutes. Add a cupful of the milk and leave it to simmer before stirring. It will form a dense mass. Add another cup of milk and let it simmer but not boil, before stirring into the floury mass. Continue adding the milk little by little until you have a smooth sauce, stirring all the time. Add the nutmeg and season. After about 20 minutes the sauce should be the consistency of double cream. Remove from the heat. Put the spinach in a colander and pour boiling salted water over it until just wilted. Drain and shake off the excess water. Spread on kitchen towels to dry. Roughly break up the ricotta with a fork into small blobs or pieces. Cut the mozzarella into slices ½cm (¼in) thick, or tear it into rough blobs. Lightly drizzle the olive oil over the bottom of an ovenproof dish measuring 23 x 33 x 5cm (9 x 13 x 2in). Scatter a third of the spinach in the dish (it doesn't have to cover the base completely), sprinkle on the marjoram or oregano (if using), and then add a third of the mozzarella and ricotta, evenly distributed. Spoon a quarter of the béchamel sauce lightly over the cheese in puddles, and cover with a layer of lasagne sheets, making sure they don't overlap. Build a further two layers the same way - that is, a third of the spinach, followed by the blobs of mozzarella and ricotta, and a quarter of the béchamel and so forth. Drizzle the remaining quarter of béchamel over the final layer of lasagne, then sprinkle the parmesan over the top. Drizzle with a little extra-virgin olive oil and bake in the oven for 30 to 35 minutes until bubbling and slightly golden on the top. In pictures: A New Year feast at Petersham Nurseries