Preheat your oven to 350°F (175°C). This ensures the bars bake evenly.

In a mixing bowl, cream together the softened butter and granulated sugar until light and fluffy. This incorporates air into the mixture, which helps the crust to be tender.

Gradually add the sifted flour and salt to the butter mixture, mixing until just combined. Avoid overmixing to keep the crust tender.

Press the dough evenly into the bottom of a greased 9x9 inch baking pan. Use your fingers or a spatula to ensure an even layer.

Bake the crust in the preheated oven for 15 minutes, or until lightly golden. This sets the crust before adding the filling.

While the crust is baking, whisk together the eggs and granulated sugar in a mixing bowl until well combined.

Add the fresh orange juice and orange zest to the egg mixture, whisking until smooth. The acidity from the juice will balance the sweetness.

Sift in the flour and baking powder, and mix until just combined. This will help thicken the filling.

Once the crust is done baking, remove it from the oven and pour the orange filling over the hot crust. This helps the filling to set properly.

Return the pan to the oven and bake for an additional 20-25 minutes, or until the filling is set and slightly firm to the touch.

Remove the baking pan from the oven and allow the bars to cool completely in the pan on a wire rack. This helps the filling to firm up.

Once cooled, dust the top with powdered sugar for a beautiful finish.

Cut into squares and serve. Enjoy your delicious orange bars!