Preheat the oven to 325°F (163°C).

In a mixing bowl, combine the graham cracker crumbs, melted butter, and ¼ cup sugar. Mix until the crumbs are evenly coated.

Press the crumb mixture firmly into the bottom of the springform pan to form the crust. Bake for 10 minutes, then remove from the oven and let cool.

In another bowl, beat the softened cream cheese and ½ cup sugar with an electric mixer until smooth and creamy.

Add the vanilla extract and mix well. Then, add the eggs one at a time, mixing until just combined after each addition.

Stir in the sour cream until fully incorporated.

Pour the cheesecake filling over the cooled crust, smoothing the top with a rubber spatula.

Bake in the preheated oven for 50-60 minutes or until the center is set but still slightly jiggly. Turn off the oven and leave the cheesecake inside for an additional hour.

Remove the cheesecake from the oven and let it cool at room temperature. Once cooled, refrigerate for at least 4 hours or overnight.

For the blackberry topping, combine the blackberries, ½ cup sugar, lemon juice, cornstarch, and water in a saucepan over medium heat.

Cook, stirring gently until the mixture comes to a boil and thickens, about 5-7 minutes.

Let the blackberry sauce cool. Once cool, spread it over the chilled cheesecake.

Slice, serve, and enjoy your Blackberry Bliss Cheesecake!