1.     Place navel oranges in a medium pot and cover with water. Bring to a boil and simmer over medium heat until extremely soft and easy to pierce with a fork, 1 to 1 ½ hours. Remove navel oranges from water and let cool completely.

2.     Remove any seeds and puree navel  orange halves in a blender until smooth. Set aside.

3.     Prepare blood oranges by cutting off ½ an inch from each end and removing peel and pith with a sharp knife. Slice into ¼-inch rounds. Set aside.

4.     Preheat oven to 325°.

5.     Heat a small saucepan over medium heat. Melt butter, then add brown sugar, lemon juice, and water. Stir continuously until sugar is melted, smooth, and sauce is slightly thickened, about 5 minutes.

6.     Pour sauce into 9-inch round (at least 2 inches deep) cake pan and set aside until set and cooled. Arrange blood orange rounds on top. Set aside.

7.     In a large mixing bowl, beat the eggs using an electric mixer, add 1 cup of navel orange puree and the orange blossom water and beat again. Add almond meal, granulated sugar, baking powder, salt, and spices. Mix thoroughly with a rubber spatula until smooth.

8.     Pour batter into cake pan and bake for 40 to 60 minutes. Beginning at 40 minutes check cake by inserting a toothpick in the center; it should come out almost clean (it’s a very moist cake).

9.     Remove and let cool in the pan before turning over onto a plate. Top with chopped pistachios and serve with a dollop of plain Greek yogurt.