Preheat oven to 350 deg. F. Grease and flour two 9" springform pans. If you prefer, line them with parchment paper.
On low speed, beat egg whites and salt in a large bowl with an electric mixer until foamy. At this point, increase mixer speed to high and beat egg whites until they form soft peaks. While still beating, add the superfine sugar one tablespoon at a time. Beat for about 8 minutes, or until you see stiff glossy peaks. Beat in lemon juice (or vinegar) and vanilla extract.
Mix together the granulated sugar, nuts and cornstarch in a small bowl, then fold this mixture into the beaten egg white mixture.
Divide meringue equally between the two prepared springforms, then spread to even out. Bake for about 30 minutes, or until the meringues are dry. Turn off the oven, remove the springform from the bottom of the pans, and leave meringues in the oven to cool for an hour (leave oven door slightly open).
After cooling in oven, meringues can be used immediately, stored tightly wrapped for a few days at room temp, or frozen for a couple of months.
Combine chocolate, butter and coffee in a small heavy-bottomed saucepan. Over low heat, stir mixture until melted and smooth. If you prefer, this can be done in a microwave instead. Once melted, allow to cool.
Halve the cherimoya and scrape the flesh into a mixing bowl using a small spoon. Mash the cherimoya flesh with a fork, hen pick out the seeds and throw them out. Mix the fruit mash with the lemon juice and pisco or brandy. Mix the berries into the cherimoya mixture.
Softly whip the cream (and stabilizer, if using) in a large bowl on low speed. Increase the speed to high and whip until stiff peaks form. Divide whipped cream in half. Fold the prepared fruit mixture into one half of the whipped cream.
Place one of the meringue disks on a serving plate with a bit of the plain whipped cream underneath to keep disk from slipping around. Drizzle the glaze over the meringue (don't spread it, though), then spread the fruit on top. Place second meringue disk over the fruit. Using a decorator bag with a 1/4" star tip, pipe 8 to 10 circles of cream around the top of the meringue disk. If using, arrange berries &/or chocolate curls on top of the torte. Sprinkle with powdered sugar (if using the chocolate curls, the powdered sugar should be sprinkled on before the chocolate for a better appearance). Chill for at least 4 hours before serving (can be chilled overnight).