Preheat the oven to 110C/90C Fan/Gas ½.
For the meringues, using a cake tin as a template, draw 4 x 20cm/8in circles onto 4 sheets of silicone paper or baking paper. Turn them over and place one sheet onto each of 4 flat baking trays.
Whisk the egg whites in a bowl until soft peaks form when the whisk is removed. Add the sugar and continue to whisk until the mixture is smooth and glossy and stiff peaks form when the whisk is removed.
Spoon the egg white mixture into a piping bag fitted with a 1cm/½in plain nozzle. Use a dot of the mixture to stick each corner of the baking paper to the tray. (This stops the paper and meringue being blown about by the oven fan.) Pipe the mixture inside each circular template, starting in the centre and working out to fill it. Smooth each meringue disc with a wet palette knife.
Cook the meringues in the oven for 2 hours. Remove from the oven to cool completely before assembling.
For the filling, whisk the cream and vanilla bean paste in a bowl until soft peaks form when the whisk is removed.
To assemble, place one meringue disc into a cake stand or large serving plate. Spread over one-third of the vanilla cream, then scatter over one-quarter of the sliced fruit. Top with a second meringue disc. Repeat the layering process, topping the last meringue disc with the remaining fruit.
To serve, melt the sugar in a heavy-based frying pan until it starts to caramelise and turn golden-brown. Stir in the flaked almonds until completely coated. Drizzle the sugared nut mixture on top of the gâteau. Chill in the fridge for about 1 hour before serving.