Preheat your oven to 350°F (175°C). Grease an 8x8-inch baking dish or line it with parchment paper.
In a medium bowl, combine the flour, powdered sugar, and salt. Add the softened butter and mix until the mixture resembles coarse crumbs.
Press this mixture evenly into the bottom of the prepared baking dish to form the crust. Bake for 15 minutes or until lightly golden.
While the crust is baking, prepare the filling by whisking together the eggs, granulated sugar, lemon zest, lemon juice, and baking powder in a large bowl.
Gently fold in the raspberries into the filling mixture.
Once the crust is done baking, pour the raspberry lemon filling over the hot crust.
Return to the oven and bake for an additional 20-25 minutes, or until the filling is set and slightly golden on top.
Allow the bars to cool completely in the pan on a wire rack. Once cooled, cut into squares and dust with additional powdered sugar if desired.