Sausage and mushroom pasticciata

1.For sausage and mushroom ragù, place mushrooms in a bowl with 375ml hot water and leave to soak. Heat oil in a large saucepan over medium-high heat, add onion and garlic and sauté until softened and translucent (4-5 minutes). Add sausage, and cook, breaking up into small pieces with a wooden spoon, until evenly browned (2-4 minutes). Deglaze pan with wine and simmer until reduced by half (2-3 minutes). Add tomato, thyme sprigs and mushrooms with their soaking liquid, season to taste and simmer, stirring occasionally, until thick and well flavoured (50 minutes to 1 hour). Discard thyme, stir in vinegar and check seasoning.

2.Meanwhile, for parmesan polenta, butter a 24cm x 33cm slice pan and line it with baking paper. Bring 1.75 litres well-salted water to the boil in a saucepan over medium-high heat and gradually add polenta, whisking continuously to combine. Reduce heat to as low as it can go and simmer, whisking occasionally, then more frequently as the mixture thickens, and cook until the polenta no longer feels grainy on your tongue (30-35 minutes). Whisk in parmesan and butter until melted and combined, then pour into prepared tray, smooth top with a wet palette knife and refrigerate until chilled and firm (1 hour).

3.Meanwhile, simmer cream in a saucepan until reduced by half (3-4 minutes), then stir in 120gm of the parmesan, season to taste and set aside.

4.Preheat oven to 180C. Cut out 6.5cm-diameter rounds from the polenta with a biscuit cutter and place a layer in the base of a lightly oiled 3.5-litre baking dish (roughly 23cm square), filling in any gaps with the polenta offcuts. Spoon ragù over, drizzle with half the parmesan cream and scatter with half the parmesan. Season, then top with another layer of polenta rounds and parmesan cream, layer mozzarella on top and scatter with remaining parmesan. Bake until golden brown and bubbling (1-1¼ hours). Stand for 15 minutes, scatter with extra thyme and serve.