Preheat oven to 350°F (175°C). Grease and line a 9x5 inch loaf pan with parchment paper.

In a food processor, pulse the pistachios with 1/2 cup of the flour until finely ground. In a medium bowl, whisk this pistachio flour with the remaining 1 cup flour, baking powder, baking soda, and salt.

In a large bowl, cream the softened butter and granulated sugar until light and fluffy (3-4 minutes). Beat in the eggs one at a time, then stir in the lemon zest and vanilla.

In a small bowl, whisk together the Greek yogurt, lemon juice, and milk.

Add the dry ingredients and the milk mixture to the butter mixture in alternating batches (begin and end with dry). Mix on low speed *just* until combined. Do not overmix.

Pour batter into the prepared loaf pan. Bake for 50-60 minutes, or until a toothpick inserted into the center comes out clean.

Let the bread cool in the pan for 15-20 minutes, then transfer to a wire rack to cool completely.

Once completely cool, whisk the powdered sugar and 2 tbsp lemon juice. Add more juice *drops* at a time to reach a very thick, gooey, and viscous consistency. Drizzle over the loaf and top with chopped pistachios. Let set before slicing.