I like to have my pistachios finely chopped so they are almost like almond meal or breadcrumbs in size. This is much easier, not to mention quicker, to do in a food processor than by hand, but be careful not to over process and end up with pistachio paste instead!
This recipe will work too with finely chopped (by hand) pistachios, however it will affect the texture of the finished bake. I would recommend having the nuts as finely chopped as possible in this cake.
You can buy pre ground cardamom powder. It is often found in the spices section of the store. If you are unable to find it, you can grind up some whole cardamom at home too. Please keep in mind that freshly ground cardamom has a much stronger flavour than pre ground, and so you will require less than stated in the recipe.
Almond extract is often used instead of vanilla in pistachio bakes, as it enhances the pistachio flavour in the bake. You can use either here, both are delicious!
Make sure to use a full fat, thick yogurt such as a Greek yogurt when making the cakes. I always use full fat milk too for best flavour in my bakes.
Once you start adding the dry ingredients to the butter/yogurt mixture, it is really important to swap to a spatula and fold the mixture to combine it. If you beat it with an electric whisk, you will end up with a gummy texture to the cake rather than a lighter fluffy one which we want.
When making the cream cheese icing, you want to use a good quality, and again a full fat cream cheese. Low fat or own brand options often have a higher water content, leading to the buttercream splitting or being a runny mess and not setting well at all.
I like to add extra chopped pistachio nuts in between the cake layers. This gives additional crunch, texture and flavour, and I love it! This is totally optional though, you can easily skip it if you wish.