01 - Preheat the oven to 350°F. Grease and line an 8x8-inch baking pan with parchment paper.
02 - In a large mixing bowl, blend the melted butter, granulated sugar, and strawberry puree until thoroughly combined.
03 - Add eggs and vanilla extract to the mixture. Whisk until smooth and fully emulsified.
04 - In a separate bowl, whisk together all-purpose flour, baking powder, and salt.
05 - Fold the dry ingredients into the wet mixture until just combined, ensuring not to over-mix.
06 - Pour the batter into the prepared baking pan and smooth the surface with a spatula.
07 - Bake for 22 to 25 minutes, or until the edges are set and a toothpick inserted into the center yields a few moist crumbs.
08 - Allow the brownies to cool completely in the pan before glazing.
09 - Whisk together powdered sugar, strawberry puree, and lemon juice (if using) until smooth and pourable.
10 - Spread glaze over the cooled brownies. Allow to set for at least 15 minutes before cutting into squares and serving.