Set the oven temperature to 180°C
Butter the base and sides of your soufflé dishes
Melt the butter and add the onion, allowing it to cook until the onion is transparent and soft, but not brown.
Add the flour and stir over the heat for 1 minute. Remove the pan from the heat and gradually add the milk, stirring to avoid lumps.
Add the seasoning and bring the mixture to boil, stirring constantly. Once it boils, stir for a further minute. This will ensure that your soufflé will not have a floury taste.
Add the herbs and ¾ of the cheese and the lemon juice. It is important to taste at this stage. Bearing in mind that you are still going to add eggs, you may want to add more salt and pepper, mustard or even a little more blue cheese, if the flavours are not good enough.
Once the mixture has cooled to room temperature, add the egg yolks to the cheese mixture and stir them in well.
Finally whisk the egg whites to soft peaks. Mix a ¼ of the whisked whites with the cheese sauce to soften the mixture, then GENTLY fold the mixture into the egg whites using a flat, flexible kitchen spoon or scraper.
Spoon the mixture into the prepared dishes.
Bake at 180°C for 12 minutes for small and 15 minutes for larger dishes.
Allow to cool for a few minutes, then loosen sides with a small palette knife and turn out onto a clean dishtowel before placing top side up in a oven proof serving dish.
Top each with about 15ml grated cheese and about 20ml cream.
Bake for about 6 minutes at 200°C just before serving