Preheat the oven to 325°F. Line a muffin tin with paper liners.
In a medium bowl, combine graham cracker crumbs, granulated sugar, and melted butter. Mix until well combined.
Press about 1 tablespoon of the mixture into the bottom of each muffin cup to form the crust.
In a large mixing bowl, beat the softened cream cheese with an electric mixer until smooth.
Add powdered sugar and vanilla extract, mixing until well combined.
Add eggs one at a time, mixing on low speed until just incorporated.
Mix in the sour cream until smooth.
Spoon the cream cheese mixture evenly over the crusts in the muffin tin, filling each cup about ¾ full.
Bake for 18-20 minutes, or until the edges are set but the center is still slightly jiggly.
Remove from the oven and allow to cool at room temperature for 30 minutes, then refrigerate for at least 2 hours to set.
Once chilled, top each mini cheesecake with chopped strawberries and blueberries.