Heat oven to 350°F (175°C). Grease a 9-inch round cake pan and line the bottom with parchment paper for easy release.
In a medium bowl, whisk together flour, baking powder, baking soda, and salt. Set aside.
In a large mixing bowl, beat softened butter with sugar for 2–3 minutes until pale and fluffy. This step incorporates air for a lighter cake.
Beat in eggs, one at a time, mixing well after each. Stir in vanilla extract.
Mix in Greek yogurt until smooth, then stir in milk. The batter will look creamy and slightly thick.
Gradually add the dry mixture to the wet mixture, stirring gently until no dry streaks remain. Avoid overmixing to prevent a dense cake.
Toss blueberries with 1 tablespoon flour to prevent them from sinking. Gently fold into the batter.
Pour batter into the prepared pan, smoothing the top with a spatula. Bake for 35–40 minutes, or until a toothpick inserted into the center comes out clean.
Let cake cool in the pan for 10 minutes before transferring to a wire rack. Dust with powdered sugar, slice, and enjoy.
