Preheat your oven to 350°F (175°C). Grease and line your 9x13-inch baking pan with parchment paper, leaving some overhang for easy removal later.
In a mixing bowl, beat together the unsalted butter and granulated sugar until creamy and light, about 2-3 minutes. Add the all-purpose flour and salt, mixing until just combined.
Press the crust mixture evenly into the bottom of the prepared pan. Bake for 18-20 minutes, or until lightly golden. Remove from the oven and let it cool slightly.
In a clean mixing bowl, whisk together the eggs and granulated sugar until well combined. Stir in the orange juice, zest, orange extract, and the flour mixed with baking powder. Mix until smooth.
Pour the filling over the pre-baked crust, spreading it evenly. Return the pan to the oven and bake for an additional 20-25 minutes, or until the filling is set and lightly golden on top.
Once baked, remove the Orange Bars from the oven and let them cool in the pan. Once cooled, lift them out using the parchment overhang and cut into squares. Dust with powdered sugar before serving.
