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