Lightly grease a 9-inch springform pan and dust with flour. (You can also make this cake in a 9-inch cake pan that has been greased and dusted with flour, and lined on the bottom with parchment paper.).
In a bowl, combine 1 cup of the flour with baking powder and salt and set aside.
Using an electric mixer on medium-high to high speed, cream the butter, sugar and vanilla until light and fluffy, about 3 minutes. Add the eggs one at a time and continue beating until well blended. Reduce the speed to low and gradually add the flour mixture. Beat until smooth. pour the batter into the prepared pan.
In a medium bowl, combine the blueberries with the remaining teaspoon of flour and the lemon juice. Spoon berry mixture over batter.
Bake for 1 hour at 350° or until a cake tester or toothpick inserted in the center comes out clean. Remove from the oven and let the cake cool in the pan for 10 minutes. If using a springform pan, slide a thin knife around the edges of the cake to release it from the pan before you release and remove the springform. (If using a cake pan, slide a knife around the edges of the cake and invert it onto a cake rack. Transfer the cake to a platter, berry side up.) Dust with confectioner's sugar before serving.