Heat oven to 375°F
Line a 12 cup muffin tin with muffin papers
Cream butter and sugar together until well blended
Add egg and vanilla, and mix well
Mix flour, baking soda and salt together in a small bowl
Add half the flour alternatively with half the milk, stir until just combined
Repeat with remaining flour and milk
Add ½ cup of blueberries and stir to break up the blueberries into the batter
Gently fold the remaining berries into the batter
Fill prepared muffin tin, filling each cup ⅔ full
Bake in preheated oven for 25-30 minutes
Cool in pan 2-3 minutes before removing from pan to cooling rack
Store in airtight container for up to 3 days
