01 - Preheat oven to 325°F. Line an 8x8-inch baking pan with parchment paper, leaving an overhang for easy removal.
02 - Mix graham cracker crumbs, sugar, and melted butter in a medium bowl until well combined. Press firmly into the bottom of the prepared pan.
03 - Bake crust for 8-10 minutes until lightly golden, then let cool while preparing the filling.
04 - Beat cream cheese and sugar in a large bowl until smooth and creamy. Add eggs one at a time, mixing well after each addition. Stir in sour cream and vanilla extract.
05 - Gently fold in diced strawberries. Pour cheesecake batter over cooled crust and smooth the top.
06 - Bake for 30-35 minutes, or until the center is just set and edges are lightly golden.
07 - Cool to room temperature, then refrigerate for at least 3 hours until fully chilled.
08 - Melt chocolate chips and butter together in a heatproof bowl over simmering water or in 20-second intervals in the microwave, stirring until smooth.
09 - Pour melted chocolate over chilled cheesecake, spreading evenly. Top with halved strawberries if desired.
10 - Refrigerate until chocolate is set, about 30 minutes. Lift bars from pan, cut into squares, and serve.