Preheat the oven to 350F. Grease and flour a bundt pan. In a stand mixer or with electric mixer, beat eggs with sugar, vanilla and orange zest until pale and slightly thickened. Meanwhile, in a separate bowl, mix flour, polenta, baking powder and salt. In a third bowl, combine olive oil and melted butter. Beat 1/3 of the flour mixture into the egg mixture, followed by 1/2 the olive oil/butter mixture, followed by another 1/3 of the flour, the rest of the olive oil and finish with the flour. Mix just until blended. Transfer batter to the prepared pan and bake for 30-40 minutes. It browns fairly easily, so it helps to give the pan a half-turn midway during the bake time. A toothpick should come out clean when done. If not, bake a few more minutes. Let cool and remove from pan. While cake is baking, make the ganache. In a large, glass measuring cup, heat the cream and corn syrup 2 minutes in the microwave, just until it starts to bubble (add or subtract time depending on the power of your microwave). Add the port, salt and chocolate chips. Stir once or twice. Let sit 3-4 minutes to allow chocolate to start to melt. Then, with a small whisk, stir until the mixture becomes smooth. Add the butter and stir to melt. Pour ganache over top of cake and allow some ganache to drizzle down the sides. Let firm up in a cool spot.