Preheat your oven to 350°F (177°C). Prepare three 8-inch round cake pans by lining the bottoms with parchment paper and spraying the sides with non-stick cooking spray.

In a large mixing bowl, combine 1 cup of sour cream, 4 large eggs, 1 cup of honey, ¾ cup of cooking oil, and 2 teaspoons of vanilla extract. Blend the ingredients on medium speed until smooth.

In a separate bowl, whisk together 2 cups of all-purpose flour, 2 teaspoons of baking soda, 2 teaspoons of baking powder, and ¼ teaspoon of salt. Gradually add this dry mixture to the wet ingredients, mixing just until combined.

Divide the batter evenly among the prepared pans. Bake for 24–26 minutes, checking for doneness with a toothpick.

Cool the cake layers in the pans for 5–8 minutes, then transfer them to a wire rack to cool completely and chill for 30 minutes.

In a food processor, blend 1 cup of shelled salted pistachios with 2 tablespoons of heavy cream until a smooth paste forms. Beat 3 cups of softened unsalted butter until fluffy, then mix in the pistachio paste and 2 teaspoons of vanilla extract. Gradually add in 4 cups of confectioner’s sugar.

Level each cooled cake layer and slice each in half horizontally for six layers. Drizzle honey on each half before adding frosting.

Start stacking the layers, spreading pistachio buttercream on each one while repeating the drizzle of honey.

Apply a thin crumb coat of buttercream around the outside of the cake and chill it in the refrigerator for about 30 minutes.

Once chilled, apply a thicker layer of pistachio buttercream around the entire cake and garnish with finely diced pistachios and a drizzle of honey.

Refrigerate the completed cake for at least 1–2 hours before serving.