Preheat the oven to 375°F. Grease a 9-inch round cake pan with oil and line the bottom with parchment paper. Oil the parchment and sprinkle 2 tablespoons of sugar to coat the bottom and sides of the pan, gently tapping the pan to shake out the excess.

In a medium bowl, whisk together the flour, cornmeal, baking powder, baking soda, and salt until combined.

In the bowl of a stand mixer fitted with the paddle attachment, beat the eggs, orange zest, and 1 cup of sugar on medium-high speed until the mixture is pale and fluffy, 4 to 5 minutes. Reduce the speed to low and slowly stream in ¾ cup of extra-virgin olive oil. Beat in the milk and orange juice. Gradually add the flour mixture, mixing just until just combined, scraping the bottom and sides of the bowl as needed.

Pour the batter into the prepared pan, smoothing the top. Sprinkle the top with the remaining 2 tablespoons of sugar.

Bake until a wooden pick inserted in the center comes out clean, 40 to 45 minutes. Transfer the cake pan to a wire rack and allow to cool 20 minutes. Remove the cake from the pan and it allow to cool completely on a wire rack.

To serve, dust the cake with powdered sugar and drizzle each slice with extra olive oil, if you like.