Step 1

Preheat oven to 350°F / 180°C and line two 8 inch cake pans

Step 2

Cream together the butter and sugar until light and fluffy

Step 3

Add eggs and beat until combined

Step 4

Add sour cream and beat until combined

Step 5

Sift the flour, baking powder, baking soda and salt and add a third of it to the batter, mix in slowly until fully incorporated

Step 6

Add half the milk and mix in until fully incorporated. Repeat with another third of the flour, the remaining milk, and then the remaining flour

Step 7

Add the pistachio paste and extracts and stir in until fully incorporated

Step 8

If you want to add a touch of green colour to the sponge, add a drop of colouring now, though it's beautiful without

Step 9

Lastly, stir the chopped pistachios into the batter - make these as fine or as chunky as you'd like

Step 10

Divide the batter between the cake pans and bake for about 45 minutes, or until a skewer inserted comes out clean

Step 11

Allow to cool completely before removing from the cake pan - this is a very soft sponge so be gentle with it

Step 12

Once the cake is cooled, start the frosting. Follow my instructions for Italian Meringue Buttercream

Step 13

Once the frosting is ready, whip in the pistachio paste and almond extract - add more or less according to taste

Step 14

Level the cakes and cut each cake in half to make four even layers

Step 15

Stack the layers, filling an even layer of pistachio Italian meringue buttercream in between each one

Step 16

Cover the entire top and sides in buttercream and decorate how you like, I just used a palette knife to create little waves in the frosting - I like how that looks with Italian meringue buttercream as it's so glossy!

Step 17

Top with some chopped pistachios of varying sizes