Nutrition per serving may change if servings are adjusted.
1½ cups apricot nectar
¾ cup dried apricots
½ cup lemon juice
2 tablespoons apricot or peach brandy
1 teaspoon unflavored gelatin
½ cup sugar
2 large egg whites
⅛ teaspoon cream of tartar
3 tablespoons water
⅓ cup whipping cream
6 amaretti cookies, crumbled
Combine apricot nectar and dried apricots in a small saucepan. Bring to a boil, reduce heat to low and simmer just until the apricots are tender, about 20 minutes.
Meanwhile, combine lemon juice and liqueur in a small bowl. Sprinkle with gelatin and set aside to soften.
Transfer the hot apricots and their cooking liquid to a food processor. Add softened gelatin; process to a smooth puree. Set a fine-mesh stainless-steel sieve over a large bowl, transfer the apricot puree to the sieve and work it through with a rubber spatula. (Discard coarse pulp.) Let the puree cool to room temperature.
Bring about 1 inch of water to a simmer in a large saucepan. Combine sugar, egg whites, cream of tartar and water in a heatproof mixing bowl large enough to fit over the saucepan. Set the bowl over the barely simmering water and beat with an electric mixer on low speed, moving the beaters around the bowl constantly, until an instant-read thermometer registers 140°F. (This will take 2 to 4 minutes.) Increase the mixer speed to high and continue beating over the heat for a full 3½ minutes. Remove the bowl from the heat and beat the meringue until cool, about 4 minutes.
Whip cream to soft peaks in a chilled bowl. Whisk about one-fourth of the meringue into the cooled apricot mixture to lighten it, then fold in the remaining meringue with a rubber spatula. Fold in the whipped cream.
Divide the mousse among 6 dessert dishes or stemmed glasses. Cover loosely and refrigerate until set, about 4 hours. Garnish with crumbled amaretti cookies before serving.