1-Preheat your oven to 350°F. Line two 9×3-inch cake pans with parchment rounds and spray with nonstick cooking spray.

2-In a small bowl, whisk together the 4 large eggs, a quarter of the 11 oz sour cream, and the 1 tsp vanilla extract and 2 tsp almond extract lightly.

3-In a large bowl, rub the zest of 1 large orange with the 14 oz granulated sugar until moist and fragrant.

4-Add the 11.5 oz all-purpose flour, 2.5 oz pistachio meal, 1 tsp baking powder, 1 tsp baking soda, and 1 tsp salt, then mix on low speed.

5-Add the 12 oz unsalted butter and the remaining 11 oz sour cream, mixing first on low speed, then on medium speed for 90 seconds.

6-Scrape the bowl and gradually add the egg mixture in three batches, beating for about 20 seconds after each addition.

7-Add green food coloring if desired for a more vibrant pistachio appearance.

8-Divide the batter evenly between the pans (about 29 oz each).

9-Bake for 35-40 minutes or until a toothpick inserted into the center comes out clean.

10-Cool on a wire rack for 15 minutes, then remove from the pans and cool completely.

1-Combine the 9 large egg whites and 14 oz granulated sugar in a heatproof bowl.

2-Set over simmering water (without touching the water) and whisk frequently until the mixture is hot and the sugar dissolves completely.

3-Remove from heat and beat with a mixer on medium-high speed until a stiff, shiny meringue forms and the mixture cools to room temperature.

4-Lower the speed and add the 1 lb unsalted butter in small chunks, waiting between additions.

5-The mixture may look separated but will come together after whipping. If not smooth after 5 minutes, chill the bowl for 5-7 minutes and whip again.

6-Add the 1 tbsp vanilla extract and ¼ tsp salt.

7-Remove about one cup of the buttercream to a separate bowl and mix in the ¼ tsp orange oil or ½-1 tsp orange extract, along with orange food coloring as desired.

8-To the remaining buttercream, add the 7 oz pistachio paste and green food coloring as desired.

9-The frostings can be refrigerated and re-whipped before use.

1-Level the tops of the cakes and slice each in half to create four layers.

2-Place the first layer on a cake board or plate.

3-Spread about 1 cup of pistachio frosting evenly on top.

4-Pipe pistachio frosting in a ring around the edge to form a dam, then fill the center with orange buttercream, spreading to the edge.

5-Add the second cake layer and spread pistachio frosting evenly on top.

6-Add the third layer and more pistachio frosting.

7-Finish with the top layer and cover the entire cake with the remaining pistachio frosting.

8-Decorate the top with the ½ cup finely chopped pistachios, 3-4 slices of candied orange peel, and pistachio and orange chocolate truffles if desired.