01 -
Preheat oven to 350°F (175°C). Grease a 9×9 inch light metal baking pan and line with parchment paper. Process pistachios in a food processor until finely ground and set aside.
02 -
In a medium bowl, whisk together flour, baking powder, baking soda, and salt. Set aside.
03 -
In a large bowl, rub lemon zest and sugar together with your fingertips to extract maximum flavor. Add softened butter and cream together on high speed for 1-2 minutes until light and fluffy.
04 -
Add eggs and vanilla to the butter mixture and mix on medium speed until pale and smooth, about 1 minute. Gradually add buttermilk and dry ingredients, mixing on low speed until just combined. Fold in the ground pistachios.
05 -
Pour batter into prepared pan and bake for 38-42 minutes, or until a toothpick inserted in center comes out clean. Cool in pan on wire rack for 30 minutes, then remove using parchment paper and cool completely.
06 -
Combine pistachio milk, sweetened condensed milk, lemon zest and vanilla in a small bowl. Let mixture infuse for 20 minutes, then strain through a sieve to remove zest, transferring to a pouring vessel.
07 -
Process pistachios in a food processor until they form a smooth paste with a nut butter consistency.
08 -
Beat butter in a large mixing bowl on high speed until pale and fluffy, about 5 minutes. Add cream cheese and mix on high speed until fluffy, about 1 minute.
09 -
Add pistachio paste and lemon zest to the butter mixture and mix on medium-high until combined. Sift in powdered sugar, mix on low until incorporated, then on high for 1 minute until fluffy.
10 -
Trim a thin layer from the top of the completely cooled cake using a sharp knife. Transfer to a serving plate and poke holes across the surface using a wooden stick or handle.
11 -
Slowly pour the pistachio milk mixture over the cake, allowing it to absorb into the holes. Spread a thick layer of lemon pistachio cream cheese frosting on top using an offset spatula. Optionally swirl lemon curd into the frosting using the back of a spoon.
12 -
Cut into 16 slices and serve.