Preheat your oven to 350°F (175°C) and line a cupcake pan with paper liners.
In a large bowl, sift together the flour, cocoa powder, baking soda, and salt to combine evenly.
In another bowl, whisk together the sugar, vegetable oil, eggs, vanilla extract, and rosewater until the mixture is smooth and slightly frothy.
Add the dry ingredients to the wet mixture in batches, mixing gently until just combined.
Fold in the pureed strawberries, ensuring they are evenly distributed and the batter turns a vibrant red hue.
Spoon the batter into the prepared cupcake liners, filling each about two-thirds full for a domed top.
Bake in the preheated oven for about 18-20 minutes, or until a toothpick inserted into the center comes out clean.
Remove the cupcakes from the oven and transfer them to a cooling rack; let them cool completely before frosting.
In a medium bowl, beat the softened butter until creamy, then gradually add the powdered sugar, mixing until smooth and fluffy.
Frost the cooled cupcakes with the strawberry frosting, smoothing the surface with a spatula for an elegant finish.
