In a small blender or food processor, puree the fresh strawberries.
Preheat the oven to 350F degrees and adjust oven rack to the middle position. Line a muffin pan with 6 cupcake liners.
In a medium mixing bowl, whisk together the flour, baking powder, salt, and sugar.
In a liquid measuring cup, measure out the strawberry puree and add stir in the egg, milk and vanilla extract. Fold the liquid ingredients and the melted butter into the dry ingredients until no dry streaks remain.
Using a cookie scoop or spoon, pour the batter into the cupcake liners about two-thirds full.
Bake for 16-18 minutes or until a toothpick inserted in the center comes out clean. Cool the cupcakes in the muffin pan for 5 minutes before transferring to a wire rack to cool completely. Allow the cupcakes to cool before frosting. The cupcakes are best enjoyed the day they are baked. Any leftovers can be stored in an airtight container at room temperature for 3 days.