Preheat the oven to 180C fan.

Heat the olive oil in a medium sauté pan over a medium heat. Add the red onion and sauté gently for around 3-4 minutes. Add the rice and toast the grains in the pan for 2 minutes. Add the wine and stir until the liquid has reduced by half.

Pour in the vegetable stock and stir well, bring to a simmer, and then reduce the heat and cover with a lid. Continue to cook for 10-12 minutes or until the liquid has been absorbed and the rice is tender. Remove from the heat and leave the lid on to stand for 5 minutes. Stir through the crème fraiche and dill. Season to taste and transfer to a bowl and pop in the fridge to cool.

Remove the stem from each of the mushrooms and discard. Place the mushrooms onto two baking trays, with the undersides facing upwards.

In a small bowl, mix the garlic with the chopped rosemary and olive oil, and then spoon over each mushroom. Add a knob of butter in the cavity of each mushroom and season with salt and pepper. Roast in the oven for 15 minutes. Remove and set aside to cool.

Heat a medium sauté pan over a high heat and add the butter and oil. When the butter begins to foam, add the shallots and sauté gently for around 5 minutes. Add the chopped thyme and chestnuts and continue to cook for 2 more minutes. Remove the pan from the heat, season well and set aside to cool.

Lay three large sheets of cling film, one on top of the other, onto your work surface.

Build a layer of rice down the middle, in a rectangle approximately 28cm long and 14cm wide. Add a layer of Brie slices, and then a layer of eight mushrooms in two rows of four, underside facing up.

Top the mushroom layer with the shallot and chestnut mixture, and then crumble over the Stilton. Place the remaining four mushrooms along the top, underside facing down.

Wrap the filling tightly by folding each side of the clingfilm over the filling, and then twisting the ends as tight as possible to form a sausage shape. Tie one end in a knot, and then push the filling tight and tie the other end. Chill in the fridge overnight, or for at least 4 hours, to set.

Line a large oven tray with greaseproof paper. Lay one of the sheets of puff pastry on the tray, then unwrap the filling fully and place it directly in the middle of the pastry. Make a diagonal cut from each corner of the pastry into the corresponding corner of the filling.

Bring the end sections of pastry up and around the filling first, followed by the sides. Overlapping the pastry and gently pressing it together will help it hold in place. Brush beaten egg between any overlapping areas of pastry.

Cut another sheet of pastry into 4cm wide strips. Starting at one end, cover the remaining filling by laying each of the strips over it crosswise, remembering to overlap the strips of pastry.

Once fully covered, brush the parcel all over with beaten egg. Cut shapes using pastry cutters and stick over the parcel to decorate. Brush these with egg wash and then sprinkle the parcel with a little salt. Place this back into the fridge to chill until you are ready to bake.

Preheat the oven to 180C fan then remove the chilled parcel from the fridge. Place on the middle oven shelf for 1 hour and 15 minutes, turning the tray halfway through. The pastry should be crispy and a deep golden colour.

Leave the parcel to rest for a few minutes and then lift carefully on to your serving platter.