Grease the bottom and sides of an 8-inch round cake pan; line with parchment paper. Grease top of paper.
Beat 1 cup sugar, eggs, olive oil, and orange juice together in a large bowl until smooth; add flour, cornmeal, orange zest, baking powder, and salt. Use a whisk to lightly mix the wet and dry ingredients together. Pour the mixture into the prepared pan. Sprinkle remaining sugar over the top of the batter.
Bake in the preheated oven until a toothpick inserted into the center comes out clean, 25 to 35 minutes. Cool cake in the pan for 20 minutes. Run a knife along the inside edge of the pan to loosen cake. Invert pan onto a plate to remove cake from pan. Use plate to again invert the cake onto a cooling rack to cool completely.