Preheat your oven to 350°F (175°C). Line your cookie sheets with parchment paper.
In a medium bowl, whisk together the all-purpose flour, cornmeal, poppy seeds, baking soda, and sea salt. Set aside.
In a large bowl, beat the unsalted butter and granulated sugar together with an electric mixer on medium speed until light and fluffy, about 2-3 minutes.
Add the lemon zest, orange zest, extra-virgin olive oil, egg, and fresh lemon juice to the butter-sugar mixture, and beat until well combined and smooth.
Gradually add the dry ingredient mixture to the wet ingredients, mixing on low speed until just combined. Avoid overmixing.
Using a cookie scoop or tablespoon, drop rounded balls of dough onto the prepared cookie sheets, leaving space between each cookie.
Before baking, sprinkle extra granulated sugar on top of each cookie.
Place the cookie sheets in the preheated oven and bake for 10-12 minutes, until the edges are lightly golden.
Remove the cookies from the oven and let them cool on the sheets for about 5 minutes before transferring them to a cooling rack.
