Preheat the oven to 350°F (175°C). Grease and flour an 8-inch round cake pan.
Place the shelled pistachios in a food processor and pulse until finely ground but not pasty. Set aside 2 tablespoons of the ground pistachios for topping.
In a medium bowl, whisk together the all-purpose flour, baking powder, baking soda, salt, and the remaining ground pistachios.
In a large bowl, beat the granulated sugar and eggs together until pale and fluffy, about 3-4 minutes.
Add the Greek yogurt, vegetable oil, vanilla extract, lemon zest, and lemon juice to the egg mixture. Mix until well combined.
Gradually fold the dry ingredients into the wet ingredients using a spatula until just combined. Do not overmix.
Pour the batter into the prepared cake pan and smooth the top with a spatula.
Sprinkle the reserved 2 tablespoons of ground pistachios evenly over the top of the batter.
Bake in the preheated oven for 40-45 minutes, or until a toothpick inserted into the center comes out clean.
Remove the cake from the oven and allow it to cool in the pan for 10 minutes.
Transfer the cake to a wire rack to cool completely.
Once cooled, dust the top with powdered sugar before serving.