Preheat oven to 400°F. Spray muffin tin with nonstick cooking spray or line muffin cups with paper cupcake liners.
In a large bowl combine flour, sugar, baking powder, baking soda and salt, stir well until all ingredient are well blended.
In another bowl, whisk together the buttermilk, butter, eggs and vanilla. Make a well in the middle of the dry ingredients and pour liquid mixture in and the strawberries.
Using a large spoon, gently fold ingredients just until moist. Do not over mix.
Spoon the batter evenly into 12 muffin cups. Sprinkle each muffin with about 1/2 teaspoon sugar, if desired.