Preheat oven to 350º. Grease a half sheet pan and line with parchment paper.
Sprinkle the raw sugar into the lined cake pan and set aside
Slice the citrus into thin rounds, about ⅛ inch thick. Arrange the citrus on top of the raw sugar, the circles should overlap slightly. Continue until the entire surface is covered.
In a stand mixer beat the butter and sugar until pale and fluffy. Add eggs one at a time until well combined, then add labneh and orange blossom water.
In a large bowl combine the cornmeal, almond flour, flour, baking powder, cardamom and sea salt. Slowly add the dry mixture to the butter mixture, stopping when mix is just combined.
Spoon the batter into the pan and use an offset spatula to spread the batter over the citrus.
Bake for 50 minutes to an hour, until a cake tester comes out clean. Allow the cake to cool for 10 minutes then turn out onto a large cutting board. Allow to cool to room temperature before serving.