In a medium bowl, combine the all-purpose flour with the baking powder and fine sea salt. Give it a stir and set it aside.
In your mixing bowl, beat together butter with the granulated sugar. Beat them until fluffy. Add in the eggs, one at a time, mixing each in completely before adding the next.
Zest part of a lemon, enough to give you 1 teaspoon of zest. Reserve the lemon. Add the zest and a teaspoon of the vanilla extract to the cream mixture. Mix it in.
Add half of the flour mixture into the cream mixture, scraping the sides of the bowl with a rubber spatula.
Next, mix in the sour cream.
Once that is mixed in, add the remaining flour mixture. Each time you add something, scrape the bowl with a rubber spatula to get everything combined and only mix it enough to blend the ingredients together.
Gently fold in 3/4 cup of the blueberries.
Spray a 9-inch cast iron skillet with baking spray or non-stick cooking spray. I prefer the baking spray with the flour in it.
Spread the batter into the prepared skillet.
Sprinkle the top with the remaining 1/4 cup of blueberries and gently press them into the batter.
Bake for 30-35 minutes or until a wooden pick inserted into the center comes out clean. Place the skillet on a rack for the cake to cool.
When the cake is cooled, you will prepare the simple glaze. Using the lemon you reserved from earlier, combine 1 1/2 tablespoon of lemon juice with the powdered sugar and remaining 1/2 teaspoon vanilla. Whisk these together until smooth.
Drizzle the glaze over the top of the cake.
Enjoy!
Notes
Frozen blueberries can be used for this recipe, however keep them in the freezer until immediately before adding them to the cake batter.