Combine graham cracker crumbs and 1/4 cup sugar in a mixing bowl. Pour in melted butter and mix until crumbs are evenly coated and hold together when pressed. Transfer mixture to a greased 9x13 inch baking pan, pressing firmly into an even layer to form the crust. Bake at 350°F (175°C) for 10 minutes or until lightly golden. Remove from oven and set aside to cool.
1 1/2 cups graham cracker crumbs, 1/4 cup granulated sugar, 1/2 cup unsalted butter
In a large mixing bowl, beat softened cream cheese with an electric mixer until smooth and creamy. Add 1 cup sugar and continue to beat until fully combined and fluffy. One at a time, add eggs, beating well after each addition. Mix in vanilla extract until just combined. Pour the cream cheese filling over the cooled crust, spreading evenly with a spatula.
16 oz cream cheese, 1 cup granulated sugar, 3 large eggs, 1 tsp vanilla extract
Bake the cheesecake at 350°F (175°C) for 40-45 minutes, until the edges are set and the center slightly jiggles when gently shaken. The top should be lightly golden. Turn off the oven and leave the cheesecake inside with the door slightly ajar for 1 hour to prevent cracking. Remove from oven and let cool completely at room temperature, then refrigerate for at least 2 hours or until fully chilled.
While the cheesecake cools, prepare the berry topping. Combine blueberries, strawberries, 2 tablespoons sugar, and lemon juice in a saucepan. Cook over medium heat, stirring frequently, until the berries release juices, and the mixture thickens slightly, about 10 minutes. Remove from heat and let cool.
2 cups mixed berries (blueberries and strawberries), 2 tbsp sugar, 1 tbsp lemon juice
Spread the cooled berry topping evenly over the chilled cheesecake. Return to the refrigerator for an additional 30 minutes to set before slicing. Cut into squares and serve with extra fresh berries if desired, showcasing the festive red, white, and blue colors.