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

In a medium bowl, whisk together the flour, baking powder, baking soda, and salt. Set aside.

In a large bowl, cream the softened butter and granulated sugar together until light and fluffy, about 3-4 minutes.

Add the eggs one at a time, mixing well after each addition. Stir in the vanilla extract.

Gradually add the dry ingredients to the butter mixture, alternating with the sour cream. Begin and end with the dry ingredients. Mix until just combined.

Fold in the chopped pistachios gently.

Pour the batter into the prepared cake pan and smooth the top. Bake for 30-35 minutes, or until a toothpick inserted into the center comes out clean.

Allow the cake to cool in the pan for 10 minutes before transferring it to a wire rack to cool completely.

For the glaze, whisk together the powdered sugar and milk until smooth. Drizzle over the cooled cake before serving.