Grate the Stilton cheese.

Blend together the Stilton cheese, curd cheese, chives, and egg yolks.

Dissolve the agar agar in the water in a pan over low heat for about 20 minutes, until completely dissolved.

Allow the agar agar mixture to cool slightly.

Stir the cooled agar agar mixture into the cheese mixture.

Add the grated lemon rind and natural low-fat yogurt to the cheese mixture.

Set aside to start thickening.

Whisk the egg whites until stiff.

Fold a small amount of the whisked egg whites into the cheese mixture to lighten it.

Gently and quickly fold in the remaining egg whites.

Check for seasoning, adding salt and pepper to taste.

Lightly grease a 1/2 pint ring mold.

Pour the mousse mixture into the prepared ring mold.

Refrigerate overnight to set.

The next day, loosen the mousse from the sides of the mold.

Invert the mold onto a serving plate.

Carefully coat the sides of the mousse ring with the minced roasted peanuts, pressing them into the surface.

Fill the center of the ring with fresh watercress before serving.