Grease the inside of a cast iron serving dish with the butter and sprinkle with 30g/1oz Parmesan.
Whisk the egg yolks with 300g/10½oz Parmesan and add the cream.
Whisk the egg whites to stiff peaks and fold through the egg yolk, cheese and cream mixture.
Tip into the serving dish and sprinkle over the remaining Parmesan. Bake for 10 minutes, or until risen.
Meanwhile, pour the wine into a saucepan placed over a medium heat. Add the pear and thyme and bring to the boil. Simmer until the pears are soft and the wine has reduced to a syrupy consistency, remove the thyme sprigs.
Remove the soufflé from the oven and serve immediately with the pears.