Preheat your oven to 350°F (175°C) and grease a 9x13 inch baking pan.
In a mixing bowl, combine flour and granulated sugar for the crumb topping. Use a pastry cutter or your fingers to cut in the cold butter until the mixture resembles coarse crumbs.
Press half of the crumb mixture evenly into the bottom of the prepared pan to form the crust. Bake for 15 minutes until lightly golden.
While the crust is baking, whisk eggs, lemon juice, lemon zest, and sugar in a bowl until smooth and slightly bubbly. Stir in the cornstarch and a pinch of salt until fully combined.
Pour the lemon filling over the pre-baked crust, spreading evenly with a spatula.
Sprinkle the fresh berries evenly over the lemon filling, pressing them down lightly into the surface.
Crumble the remaining dough over the berries, covering the entire surface for that crunchy topping.
Bake the assembled bars for 25–30 minutes until the topping is golden brown and the filling is bubbling around the edges.
Remove the bars from the oven and let them cool completely in the pan on a wire rack; this helps the filling set and makes cutting easier.
Slice into squares with a sharp knife, revealing the vibrant berries, bright lemon filling, and crunchy topping.
Enjoy these bars at room temperature or chilled — they’re perfect for a light dessert or snack anytime!
