Chocolate Meringue Mousse Cake

Meringues10 large egg whites
1 1/2 cup sugar
1 cup Valrhona unsweetened cocoa powder, sifted

To make the white chocolate mousse

1. Preheat oven to 250 F with racks in upper and lower thirds. Line 2 large baking sheets wth parchment paper and draw 3 (7"x5") ovals on 1 lined pan.
   
2. Whisk together egg whites and sugar in mixer bowl, then set bowl over a large suacepan of barely simmering water and heat whites, whisking constantly, until mixture is foamy and registers 122 to 125 F on an instaread thermometer.
   
3. Beat whites with mixer until they hold stiff peaks. Remove bowl from mixer and sift cocoa powder over meringue, then fold in gently but thoroughly (mixture will deflate).
   
4. Transfer to pastry bag with 1/2" round tip and starting from the center of each oval, pipe meringue in a tight spiral to fill ovals to outer edge.
   
5. Pipe as many 2 1/2" strips (about 1/3" wide and 1/2" apart) as possible on second lined pan, slanting rows so more strips will fit.
   
6. Bake meringues, switching position of pans halfway through baking, until dry, crisp, and firm, 3 to 4 hours. (They're done when they release from the parchment.
   
7. Slide parchment with meringues onto a rack to cool completely.
   

Filling
2 large eggs, plus 1 egg yolk
1/3 cup sugar, divided
1 1/2 tbsp water
6 ounces Valrhona chocolate (no more than 62% cacao)
1 cup chilled heavy cream
3 tbsp seedless raspberry jam

To make the filling

1. Whisk together eggs and yolk with 2 tsp sugar in a bowl.
   
2. Bring water and remaining sugar to a boil in a small heavy saucepan over medium heat, stirring until sugar has dissolved.
   
3. Pour slowly into egg mixture, whisking, then return mixture to saucepan.
   
4. Cook over medium-low heat, whisking constantly, until mixture is very thick and eggs just begin to curdle on bottom of pan, about 2 minutes.
   
5. Beat in cleaned mixer bowl (with cleaned whisk attachment) at high speed until mixture is doubled and cooled to room temperature, about 5 minutes.
   
6. Melt chocolate, then remove from heat and cool to warm (about 105 F), stirring occasionally.
   
7. Meanwhile, whisk cream in a large bowl until it just holds soft peaks.
   
8. Fold chocolate into egg mixture, then quickly fold in whipped cream.
   

Assembly

1. Trim meringue ovals to same size.
   
2. Dab some mousse (to secure meringue) in center of a serving plate, then set 1 oval on top.
   
3. Spread with about 1 cup mousse, then top with another oval.
   
4. Spread with jam, then another cup of mousse, and top with reamining oval.
   
5. Chill 15 minutes (do not chill remaining mousse).
   
6. Frost cake with reamining mousse, then gently press meringue strips diagonally around side of cake.
   
7. Chop remaining strips and scatter on top.
   
8. Chill cake, loosely covered with plastic wrap, 8 to 24 hours. Let stand, covered, at room temperature 30 minutes prior to serving.