Preheat the oven to 350°F and position a rack in the center.

Brush the bottom and sides of a 9-inch round cake pan with olive oil, line the bottom with parchment paper, and dust with flour.

In a medium bowl, whisk together flour, salt, baking powder, and baking soda.

In a large bowl, combine granulated sugar, cardamom, and eggs, then beat until thick and fluffy, about 5 minutes. Slowly drizzle in olive oil while mixing. Reduce speed and add half the orange zest, orange juice, and milk. Beat until smooth.

Add the flour mixture to the wet ingredients and mix on low until a uniform batter forms.

Pour the batter into the prepared pan and sprinkle the top with the remaining granulated sugar. Bake for 40 to 45 minutes or until a skewer inserted in the center comes out clean.

Allow the cake to cool for 30 minutes in the pan, then invert onto a plate and cool completely on a rack.

Dust the cake with sifted confectioners' sugar and sprinkle with orange zest before serving.