Preheat oven to 350°F (175°C).
Line an 8×8 inch baking pan with parchment paper, leaving an overhang on the sides.

For the Crust:
In a medium bowl, whisk together flour, sugar, and salt.
Cut in the chilled butter using a pastry blender or your fingertips until the mixture resembles coarse crumbs.
Press the crumb mixture evenly into the bottom of the prepared baking pan.
Bake for 15-18 minutes, or until lightly golden.
Remove from oven and let cool slightly.

For the Filling:
In a large bowl, beat the softened cream cheese and sugar until smooth.
Beat in the eggs one at a time until well combined.
Stir in the flour, lemon juice, lemon zest, and vanilla extract until just combined. Do not overmix.
Gently fold in the fresh blueberries.
Pour the filling evenly over the baked crust.

Bake for 25-30 minutes, or until the edges are set and the center is slightly jiggly.
Let the bars cool completely in the pan on a wire rack.
Once cooled, chill in the refrigerator for at least 2 hours before cutting into bars.
Cut into desired portion sizes.