Preheat oven to 375℉. Generously grease a 9-inch round cake pan using olive oil.
In a large bowl, mix together flour, salt, baking powder, and baking soda. Set aside.
In the bowl of a stand mixer (can also use a hand mixer), combine sugar, eggs, and lemon zest. Mix on high for about 5 minutes until mixture turns pale yellow.
Slowly add olive oil. Mix for another 2 minutes.
Reduce mixer to low speed. Add milk, lemon juice, and Limoncello (or Grand Marnier). Mix until everything is combined. Do not overmix.
Gradually add the flour mixture. Fold to combined. Avoid overmixing.
Pour batter into prepared pan. Bake for 45-48 minutes or until an inserted toothpick comes out clean.
Leave cake in the cake pan and place cake pan on a cooling rack. Let it cool for 20 minutes. Run a knife along the outer edge of the cake to help release the cake from the pan. Invert the cake onto a plate or cake stand and gently lift and remove the pan. Let cake rest and cool completely.
Sprinkle the tops of the cake with powdered sugar. Serve and enjoy!