Whisk the egg whites until they form stiff peaks, add the sugar, whisking all the time, then keep whisking until the mixture is thick and glossy, and fold in the nuts.
Whip the cream until it is stiff and sandwich the meringues together.
Pipe small rounds of the mixture on 2 baking trays lined with non-stick parchment and bake for 1 hour (for soft centres) or 1½ hours for crisper ones. Leave to cool in the oven. Repeat with any more mixture.