01 - Preheat oven to 350°F. Grease and line a 9-inch round cake pan with parchment paper.
02 - Whisk together flour, ground pistachios, baking powder, and salt. Set aside.
03 - Beat butter and sugar until pale and fluffy, approximately 3 minutes.
04 - Incorporate eggs one at a time, beating thoroughly after each addition. Blend in vanilla extract.
05 - Add half of dry ingredients to wet mixture and mix gently. Pour in milk, then add remaining dry ingredients, mixing until just combined.
06 - Gently fold raspberries into batter, taking care not to crush them.
07 - Pour batter into prepared cake pan and smooth top evenly.
08 - Bake for 38-42 minutes, or until toothpick inserted into center comes out clean.
09 - Let cake cool in pan for 15 minutes, then transfer to wire rack to cool completely.
10 - Dust with powdered sugar and sprinkle with chopped pistachios if desired.