Strawberry-Blueberry Napoleons

Ingredients

• 0.7 cup balsamic vinegar 
• 2 pint blueberries fresh
• 1 cup cup heavy whipping cream chilled
• 1 pound mascarpone cheese 
• 0.8 pound sheets dough fresh frozen thawed ()
• 12 servings powdered sugar 
• 3 pint strawberries fresh hulled thinly sliced
• 16 teaspoons sugar 
• 6 tablespoons butter unsalted melted ()
• 2 teaspoons vanilla extract 

Equipment

• baking sheet
• sauce pan
• baking paper
• oven
• mixing bowl
• plastic wrap
• kitchen towels
• spatula
• drinking straws

Directions

1. Preheat oven to 350°F. Line 2 large baking sheets with parchment paper.
2. Place 1 phyllo sheet on work surface (cover remaining phyllo with plastic wrap, then damp kitchen towel).
3. Brush phyllo sheet with some melted butter and sprinkle with 1/2 teaspoon sugar. Top with second phyllo sheet.
4. Brush with some melted butter and sprinkle with 1/2 teaspoon sugar. Repeat with 2 more phyllo sheets, brushing each with melted butter and sprinkling each with 1/2 teaspoon sugar.
5. Cut phyllo stack in half lengthwise; cut crosswise into thirds, creating six 4 1/4-inch squares.
6. Transfer squares to 1 prepared baking sheet, spacing evenly apart. Repeat with 4 more phyllo sheets to create 6 more squares; transfer to second baking sheet, spacing evenly apart.
7. Bake phyllo until light golden, about 7 minutes. Using spatula, transfer phyllo stacks to rack and cool completely. Repeat with remaining phyllo sheets, butter, and sugar to make 36 squares total. (Phyllo squares can be made up to 2 days ahead. Store between layers of waxed paper in airtight container at room temperature.)
8. Bring vinegar and 4 teaspoons sugar to boil in small saucepan over medium-high heat. Reduce heat to low and simmer until syrupy and reduced to 1/4 cup, about 25 minutes. Refrigerate until cold, about 1 hour. (Can be prepared 1 day ahead. Refrigerate.)
9. Beat mascarpone, cream, vanilla extract, and remaining 1/2 cup sugar in large mixing bowl until stiff peaks form. (Mascarpone filling can be prepared 1 day ahead. Cover and refrigerate.)
10. Set aside 1/4 of strawberries and blueberries for garnish.
11. Place 12 phyllo squares on work surface.
12. Spread each with 1 tablespoon mascarpone filling. Cover with remaining sliced strawberries.
13. Spread 1 tablespoon filling over strawberries.
14. Place another 12 phyllo squares atop filling with corners slightly askew to bottom square.
15. Spread each square with 1 tablespoon filling. Cover with remaining blueberries.
16. Spread 1 more tablespoon filling over blueberries. Top with final 12 phyllo squares with corners slightly askew to middle square. (Can be made 3 hours ahead.
17. Place napoleons on 2 large baking sheets. Cover and refrigerate.)
18. Spoon dollop of filling atop each napoleon.
19. Garnish with reserved straw-berry slices and blueberries. Dust with powdered sugar.
20. Place 1 napoleon in center of each plate.
21. Drizzle balsamic reduction around edge of plates.
22. *Italian cream cheese, available at Italian markets and many supermarkets.