01 - Preheat oven to 350°F. Grease and line an 8x8-inch baking pan with parchment paper.
02 - In a large bowl, combine melted butter, granulated sugar, and strawberry puree. Whisk until blended.
03 - Add eggs and vanilla extract to the mixture and whisk until smooth.
04 - In a separate bowl, whisk flour, baking powder, and salt until evenly mixed.
05 - Fold dry ingredients into the wet mixture just until combined. Avoid over-mixing.
06 - Pour batter into the prepared pan and smooth the top with a spatula.
07 - Bake for 22 to 25 minutes, or until edges are set and a toothpick inserted in the center comes out with moist crumbs.
08 - Allow to cool completely in the pan.
09 - In a small bowl, whisk powdered sugar, 2 to 3 tablespoons strawberry puree, and lemon juice, if using, until smooth and pourable.
10 - Spread glaze over cooled brownies. Set for 15 minutes, then cut into squares and serve.