Preheat your oven to 350°F (175°C). Grease and flour two 9-inch round cake pans.

Cream together the softened butter and granulated sugar until light and fluffy, about 3–4 minutes.

Incorporate the eggs one at a time, mixing well after each addition. Stir in the vanilla extract and rose water.

Whisk together the flour, baking powder, baking soda, salt, and ground pistachios in a separate bowl.

Combine the wet and dry mixtures by gradually adding the dry ingredients, alternating with the milk.

Divide the batter evenly between the prepared cake pans and smooth the tops.

Bake for 30–35 minutes, or until a toothpick inserted into the center comes out clean.

Beat the softened butter in a bowl until creamy. Gradually add powdered sugar and mix on low speed.

Layer one of the cooled cakes on a serving plate. Spread a layer of frosting on top.

Stack the second layer of cake on top and frost the top and sides with remaining frosting.

Decorate the top of the cake with chopped pistachios and additional rose petals if desired.

Slice and serve the cake chilled or at room temperature.