Step 1: Brine the Oranges (Optional, but Highly Recommended). In a small bowl, combine the dill pickle brine and water. Add whole oranges to the brine. Let them sit at room temperature.

Step 2: Preheat Oven and Prepare Pan. Preheat the oven to 375°F (190°C). 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.

Step 3: Whisk Dry Ingredients. In a medium bowl, whisk together the flour, cornmeal, baking powder, baking soda, dill pickle powder, and salt until combined.

Step 4: Beat Eggs, Sugar, and Zest. In the bowl of a stand mixer fitted with the paddle attachment, beat the eggs, orange zest (zest the brined oranges after removing them from the brine and drying them), and 1 cup of sugar on medium-high speed until the mixture is pale and fluffy, 4 to 5 minutes.

Step 5: Add Oil, Milk, and Juice. Reduce the speed to low and slowly stream in ¾ cup of extra-virgin olive oil. Beat in the milk and orange juice.

Step 6: Add Dry Ingredients. Gradually add the flour mixture, mixing just until just combined, scraping the bottom and sides of the bowl as needed.

Step 7: Pour Batter into Pan. Pour the batter into the prepared pan, smoothing the top. Sprinkle the top with the remaining 2 tablespoons of sugar.

Step 8: Bake. Bake until a wooden pick inserted in the center comes out clean, 40 to 45 minutes.

Step 9: Cool. 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.

Step 10: Serve. To serve, dust the cake with powdered sugar and drizzle each slice with extra olive oil, if you like. Garnish with fresh dill, if desired.