Lightly toast the walnuts in a naked frying pan. over a low flame. Set aside.
Peel, quarter, and core the fresh quince.
Cut the fruit into very small pieces.
Add the fresh quince pieces to the pan, and sprinkle with the brown sugar.
Cook, stirring frequently until caramelized. Let cool completely.
Cut the camembert cheese into small pieces. Combine with the cream cheese.
Mix in 2 tablespoons each of the walnuts and quince.
Season with salt and freshly ground pepper to taste.
Transfer the mixture to a serving bowl. Cover with plastic cling film and chill until ready to serve.
Garnish with the remaining walnuts before serving.