Preheat your oven to 350°F (175°C) and line a muffin tin with cupcake liners.
In a medium bowl, whisk together the flour, baking powder, baking soda, and salt. Set aside.
In a large bowl, beat the softened butter and granulated sugar together until light and fluffy, about 3-4 minutes.
Add the eggs one at a time, mixing well after each addition. Then mix in the vanilla extract and lemon zest.
Slowly add the lemon juice and buttermilk alternately with the dry ingredients, starting and ending with the flour mixture. Gently fold in the pureed strawberries until just combined.
Spoon the batter into each cupcake liner, filling them about 2/3 full.
Bake in the preheated oven for 18-20 minutes, or until a toothpick inserted into the center comes out clean. Let the cupcakes cool in the pan for 5 minutes before transferring to a wire rack to cool completely.
For the frosting, beat together the powdered sugar and lemon juice until smooth and fluffy. Adjust the consistency with a little water if needed.
Once the cupcakes are completely cooled, frost them generously with the lemon frosting. If desired, top with a slice of fresh strawberry for garnish.
Notes
Top with a slice of fresh strawberry for garnish if desired.