Pre-heat oven to 400°F.
Place cup liners in an eight-muffin tin.
In a medium bowl, cream butter and sugar; add egg; mix well.
In a small bowl, sift flour, baking powder, and salt.
Add some of the flour mixture; then some of the milk, to the butter mixture; alternating until all has been added; thoroughly combine after each addition.
Add vanilla and gently stir in strawberries.
Spoon batter into muffin pans.
In a small bowl, combine sugar and cinnamon; sprinkle over muffins.
Bake for 20 – 25 minutes.
Remove from oven, place on a cooling rack, for 10 minutes, before removing from muffin tin.
