Boil the pasta according to the package instructions, drain and set aside and preheat the oven to 200ºC.

Heat 2 tablespoons of the olive oil in an ovenproof pan, skillet or baking dish over high heat.  Once the oil is hot add in the mushrooms and pan-fry until they’re a deep brown and colouring on all sides. Remove the mushrooms from the pan and place them in a bowl. 

Heat the butter and remaining oil in the pan and sauté the onion and garlic until soft and translucent, about 5 minutes. Add in the thyme and rosemary and continue to sauté for another 2 minutes. Pour the cream and milk into the pan and bring to a gentle simmer.

Add 75g of the grated cheddar reserving the remaining cheese for the topping. Whisk the cheese into the sauce until smooth. Add the mushrooms to the sauce and stir well. Gently stir the cooked pasta into the mushroom sauce and taste and adjust the seasoning.

Sprinkle the mozzarella and remaining cheddar over the pasta and bake in the preheated oven for about 10 minutes until the cheese is golden and bubbling and the sauce is starting to bubble up around the edges.