Stars and Stripes Grand Finale Cake

In a bowl, combine half of the strawberries with 1/2 cup of sugar and 1 envelope of gelatin. Let sit at room temperature for about 15 minutes, allowing the juices to develop and the sugar and gelatin to partially dissolve. Microwave on high for 2 minutes, or until the gelatin is fully dissolved. Stir well to incorporate, then gently fold in the remaining strawberries. (Estimated time: 20 minutes)

In a separate bowl, mash 1 cup of the blueberries with the back of a fork. Stir in 1/2 cup of sugar and 1 envelope of gelatin. Let sit at room temperature for about 15 minutes to allow the juices to develop and the sugar and gelatin to partially dissolve. Microwave for about 2 minutes, or until the gelatin is melted. Stir to blend thoroughly, then mix in the remaining blueberries. (Estimated time: 20 minutes)

Tightly cover the bottom and sides of a springform pan or a tall tube pan with a removable bottom with aluminum foil, ensuring a secure seal to prevent any juice leakage. (Estimated time: 5 minutes)

Pour the entire strawberry mixture into the prepared cake pan, creating an even layer at the bottom. Cover the strawberry layer completely with slices of angel food cake, tearing or cutting pieces as needed to create a tight, uniform layer. Spread one container of thawed whipped topping evenly over the first cake layer. Create a second layer of angel food cake, pressing the pieces together to form a solid layer. Pour the blueberry mixture evenly over the second cake layer. Arrange a third and final layer of angel food cake on top of the blueberries, and spread the remaining container of whipped topping evenly over the top layer. Finish with a final layer of angel food cake. (Estimated time: 30 minutes)

The layered cake will likely extend beyond the edge of the pan. Carefully cover the cake with a large piece of aluminum foil, and place a baking sheet on top. Invert the cake onto the baking sheet, pressing firmly to ensure it settles evenly. Weigh down the mold using pie weights or bags of dry beans or rice. Refrigerate for at least 8 hours, or preferably overnight, to allow the cake to set completely. (Estimated time: 8+ hours)

Before unmolding, soak a clean kitchen towel in very hot water, wring out the excess, and wrap the hot towel around the cake pan. Let it sit for about 1 minute to gently warm the sides of the pan. Remove the towel. Holding the pan and plate together, gently shake the cake back and forth to loosen it from the sides of the pan. Carefully open the springform ring, or gently pull back the sides of the tube pan. Avoid forcing the cake; if it sticks, repeat the hot towel procedure. (Estimated time: 10 minutes)