Preheat oven to 400 degrees. Place muffin liners in muffin tin.

In a large mixing bowl, combine flour, sugar, baking powder and salt.

Using a pastry blender, cut in butter until mixture resembles fine crumbs. If you don't have a pastry blender just use a fork.

In a small bowl, beat together egg, milk, lemon juice and vanilla extract.

Add egg mix to the dry mix just until blended.

Fold in blueberries.

Divide batter into each muffin cup.

Bake at 400 degrees for 20 minutes. Enjoy!