Preheat the oven to 350°F (175°C). Line a 9x13-inch baking pan with parchment paper and lightly grease it.
In a medium bowl, combine the flour, sugar, salt, and melted butter until crumbly.
Press the crust mixture firmly into the prepared pan and bake for 15 minutes.
Meanwhile, beat the softened cream cheese and sugar until smooth.
Add the eggs one at a time, then mix in the vanilla extract until fully combined.
In a separate bowl, gently toss the blueberries with the cornstarch, lemon juice, and sugar.
Spread the cream cheese filling evenly over the baked crust.
Scatter the blueberry mixture over the filling, pressing the berries lightly into the surface.
Bake for 35–40 minutes, or until the center is just set and the edges are lightly golden.
Cool completely, then refrigerate for at least 2 hours before slicing into bars.