01 - Preheat the oven to 350°F. Line an 8x8-inch baking pan with parchment paper, leaving overhang for easy removal.
02 - In a large bowl, whisk melted butter and granulated sugar until smooth. Add eggs, vanilla extract, lemon zest, and lemon juice. Whisk until well combined.
03 - In a separate bowl, whisk together flour, baking powder, and salt.
04 - Gradually fold dry ingredients into the wet mixture until just incorporated. Do not overmix.
05 - Gently fold in raspberries, being careful not to crush them.
06 - Spread batter evenly into prepared pan and smooth top. Bake for 28-32 minutes until edges are golden and a toothpick inserted in center comes out with moist crumbs. Do not overbake.
07 - Allow blondies to cool completely in the pan on a wire rack.
08 - Whisk together powdered sugar, lemon juice, and lemon zest until smooth and pourable.
09 - Drizzle glaze evenly over cooled blondies. Let set for at least 10 minutes, then cut into 16 squares and serve.