Preheat oven to 350°F degrees and place the Medium Round Mold on a Medium or Large Perforated Baking Sheet and set aside.
With the skin still on, slice citrus ½ inch thick. Use a paring knife to carefully remove the skin from the citrus slices (just cutting off the outer ring/layer) You want to keep the citrus segments intact so they don’t break apart.
In the Mini Cake Mold, microwave the ½ cup granulated sugar and the ¼ cup water until the sugar completely dissolves, about 45 seconds. Pour half of the sugar water into the bottom of the Medium Round Mold, then line the bottom with the sliced citrus fruits (alternate what you put next to each other so they are all mixed). Once arranged, pour the remaining sugar-water over the citrus and set aside.
In the Stainless Mixing Bowl, using a hand mixer(or can use your stand mixer), cream together the butter and sugars together until light and fluffy. Add in the eggs, orange juice, orange zest and vanilla extract and combine until all is fully incorporated.
In a separate bowl, whisk together the flour, baking powder, baking soda, and salt. Slowly alternate folding in the flour mixture and the yogurt into the wet ingredients until everything is combined. Mixture will be thick.
Pour the batter over the prepared citrus slices, spreading it evenly to the edges. Bake for 35 minutes, then allow to cool completely before flipping out onto a cake stand or serving platter.