For the fruit base: Heat oven to 350°F. Grease a 9" cake pan with cooking spray. Line with a round of parchment and spray with cooking spray. Sprinkle parchment evenly with sugar. Arrange citrus slices in the bottom of the pan, overlapping slightly if needed. Sprinkle with POM Wonderful Pomegranate Arils to fill the areas between the citrus slices.
For the cake: In a medium bowl, whisk together the almond flour, flour, baking powder, baking soda, and salt. Set aside.
In the bowl of a stand mixer fitted with the whisk attachment, add the eggs and sugar and beat on medium-high speed until thickened and foamy, like soft whipped cream, 3–5 minutes.
Once whipped, add the Halos zest, POM Wonderful 100% Pomegranate Juice, olive oil and vanilla and beat on medium-low speed until combined. Add the flour mixture gradually on low speed and then increase the speed to medium-low, beating until incorporated.
Pour the cake batter over the citrus wheels. Bake for 35–40 minutes until a toothpick inserted in the center comes out clean.
Transfer cake to a wire baking rack and run an offset spatula around the rim while still warm. Once cooled, place a platter on top of the cake pan and invert to flip out.
For the garnish: In the bowl of a stand mixer fitted with the whisk attachment, add the cream and sugar. Whip until medium peaks form, 3–4 minutes. Serve cake topped with whipped cream, POM Wonderful Pomegranate Arils, and Wonderful Pistachios.
