Flag Cheesecake Bars

16 tablespoons (2 sticks) unsalted butter, melted and cooled, plus more for the pan

4½ cups finely ground chocolate waters, such as Nabisco Famous (2 packages; from about 80 wafers)

1 cup chilled heavy whipping cream

1 pound cream cheese, at room temperature

8 ounces mascarpone cheese, at room temperature

2 tablespoons fresh lemon juice (from 1 lemon)

2 teaspoons vanilla extract

¾ cup confectioners' sugar

Fresh blueberries, for garnish (see note)

Fresh raspberries, for garnish (see note)

Preheat the oven to 350 degrees. Use a little butter to grease the sides of a rimmed baking sheet.

Combine the melted butter and ground chocolate wafers in a mixing bowl, stirring until evenly coated. Press the mixture evenly over the bottom of the sheet and about halfway up the sides.

Bake (middle rack) for about 10 minutes, until the crust is slightly puffed. Transfer the pan to a wire rack to cool completely.

Meanwhile, pour the heavy whipping cream into the bowl of a stand mixer fitted with balloon-whisk attachment or into the bowl for a handheld electric mixer. Beat on high speed, just until firm peaks form. (Pull off the whisk attachment or the beaters out and see how the cream looks in the bowl and on the beaters. If it flops over, it needs more time; if it holds its shape, you're set.) Transfer the whipped cream to a container; cover and refrigerate until you're ready to use it.

Combine the cream cheese and mascarpone in the same mixer bowl (no need to wipe it out); use the mixer's paddle attachment and beat on medium speed until smooth and well incorporated. Add the lemon juice and vanilla extract; beat (medium speed) until smooth. Stop to add the confectioners' sugar; beat on low speed until thoroughly incorporated.

Use a flexible spatula to gently fold in half the whipped cream. Lift the cream cheese-mascarpone mixture from the bottom of the bowl over the top of the whipped cream, rotating the bowl as you work and trying not to deflate the whipped cream too much. This folding step will help lighten the cheese mixture. Then fold in the remaining whipped cream. This is your filling.

Use an offset spatula or spoon to spread the filling evenly over the cooled crust. Decorate with the berries and refrigerate for a few hours to cool and firm up. If you are making the bars a day in advance, wait to apply the berries to avoid any pooling of juices. The bars need to be refrigerated a few hours to firm up. Without the final application of berries, the bars can be refrigerated up to overnight.

Cut into squares and serve.

Note: The number of berries required will vary based on which baking sheet size, and design, you choose. We used blueberries and raspberries to build the American flag motif. Seasonal strawberries would be a worthy red-fruit substitute.

Makes 24 bars; makes enough to fill one half-sheet pan or two quarter-sheet pans

Nutrition | Calories: 310; Total Fat: 25 g; Saturated Fat: 14 g; Cholesterol: 70 mg; Sodium: 220 mg; Total Carbohydrates: 20 g; Dietary Fiber: 1 g; Sugars: 11 g; Protein: 3 g.

From Washington Post staff writer Becky Krystal; crust recipe adapted from "Gourmet Today: More Than 1000 All-New Recipes for the Contemporary Kitchen," edited by Ruth Reichl (Rux Martin/Houghton Mifflin Harcourt, 2009).