Thinly slice the onions and saute in a the 1butter till well browned. Add the sugar about 10 minutes into the process. Totally it would take about 15-20 min over medium-high heat. Set aside.

Melt the butter in a large saucepan and use some to grease 6 x 200ml soufflé dishes or one large ceramic dish. Place the remaining butter back on the heat, then scatter over the flour and mix well.

Cook for 2 mins, stirring constantly, then gradually whisk in the warm milk, a little at a time, until you have a thick, smooth mixture.

Stir in the Parmesan, mustard and thyme, then set aside to cool slightly. Beat in the egg yolks, fold through the goat’s cheese, season with salt and pepper, then transfer to a large bowl.

In a clean bowl, whisk the egg whites until they just start to stiffen and hold peaks. Use a metal spoon to fold them into the cheesy mixture, in 3 additions.

Heat oven to 200C/180C fan/gas 6. Spread the onions onto the bottom of the dishes then spoon over the egg-cheese mixture. then sit them in a roasting tin. Pour boiling water into the tin to reach halfway up the sides of the dishes.

Bake the soufflés for 20-25 mins (or 30 min if using large dish)until they are risen and coloured. Remove the dishes and set aside for 10 mins. Run a knife around the edges, then turn out onto the serving dish and serve hot.