Meringue Napoleons with Lime Ice Cream and Blackberries

Ingredients

• 5 oz blackberries 
• 3 large egg whites 
• 6 servings lime ice cream 
• 6 servings accompaniment: lightly whipped cream sweetened
• 6 servings lime zest fresh finely grated
• 0.1 teaspoon salt 
• 2 tablespoons sugar 

Equipment

• food processor
• bowl
• baking sheet
• baking paper
• oven
• knife
• sieve
• blender
• hand mixer
• offset spatula

Directions

1. Preheat oven to 175°F and line 2 large baking sheets with parchment paper. Make a template for meringues. First, trace a 5-inch square from cardboard and cut to size. Then trace a 3-inch square in center, and cut out with X-Acto or utility knife.
2. Beat whites with salt in a bowl with an electric mixer at medium-high speed until they just hold soft peaks. Gradually add half of sugar, beating at high speed, and continue to beat until whites hold stiff, glossy peaks. Fold in remaining sugar gently but thoroughly.
3. Spread about 1 teaspoon meringue onto corners of each piece of parchment and turn paper over, pressing on corners to adhere parchment to baking sheets.
4. Starting in 1 corner, place template flat against 1 baking sheet and spoon a heaping tablespoon meringue into center. Holding template down firmly, spread meringue evenly with offset spatula to fill opening, then gently lift template straight up from sheet to make a clean edge. Form 17 more meringues in same manner (9 per sheet), scraping excess meringue from template as necessary. Discard any leftover meringue.
5. Bake in upper and lower thirds of oven until dry to the touch, very pale, and crisp, about 1 1/4 hours. Cool meringues on sheets 5 minutes, then carefully peel meringues from parchment and transfer to racks to cool.
6. Purée berries with sugar (to taste) in a blender or food processor, then force through a fine sieve into a bowl to remove seeds.
7. Sprinkle 6 meringue squares with confectioners sugar. Put 1 unsugared meringue square on each of 6 plates and top with small scoops of ice cream and berries, then cover with a sugared meringue square. Spoon a dollop of whipped cream onto each napoleon and grate a bit of lime zest over top. Divide sauce among plates.
8. · Meringues (without confectioners sugar) can be made 4 days ahead and kept in an airtight container at room temperature. · Blackberry sauce can be made 1 day ahead and chilled, covered.