serves 4 - 6
3 oz (75 g) hazelnuts (filberts)
3 egg whites
2/3 cup (150 g) 5 oz caster sugar (superfine granulated)
2 - 3 drops vinegar
2 - 3 drops vanilla essence
for the filling and topping
125 ml (4 fl oz) double cream (heavy cream)
1-2 tsp (5 - 10 ml) caster sugar (superfine granulated)
1. Reserve a few hazelnuts for decorating the gateau.
2. Bake the rest in a preheated 180°c (350°f) gas 4 oven for 10 minutes.
3. Rub off the skins. Chop the nuts very finely or process briefly in a blender or food processor. Set aside. Do not turn off the oven.
4. Line two baking sheets with greaseproof paper or non stick baking parchment.
5. Draw a 15 cm (6 inch) circle on each and very lightly oil the greaseproof paper, if used.
6. Combine the egg whites and caster sugar in a heatproof bowl.
7. Set over a saucepan of gently simmering water and whisk until the meringue mixture is very thick and holds its shape.
8. Add the vinegar, vanilla essence and chopped nuts.
9. Spread the meringue inside the marked circles or place it in a piping bag with a 1 cm (1/2 inch) plain nozzle.
10. Starting from the middle of one circle, pipe round and round to form a coiled, flat round 15 cm (6 inch)es in diameter.
11. Pipe a similar round on the other sheet.
12. Bake for 35 - 40 minutes, until each layer is crisp and lightly browned. Leave to cool.
13. Whip the cream in a bowl until it stands in stiff peaks, then stir in caster sugar to taste.
14. Place one of the meringue rounds on a serving plate and spread with most of the cream.
15. Put the second meringue round on top and decorate with the rest of the cream and the reserved hazelnuts.