Pre-heat oven to 350°F.
Grease a 10-inch spring form pan well and line the bottom with parchment paper, if you like, for easy release of the cake when it is baked.
In a medium bowl, cream together the butter and sugar until light and fluffy.
Add the eggs, one at a time; beat well after the addition of each egg.
Beat in the vanilla extract.
In a medium bowl, sift together the flour and baking powder.
Add dry ingredients, alternately with the milk; begin and end with an addition of dry ingredients; as a general rule, add the flour mixture in 3 divisions and the milk in two.
Be careful not to over mix the batter or your cake will be dense.
Fold the batter only until the flour is incorporated but no more.
Quickly fold in the blueberries.
Spread batter evenly into the prepared pan.