• Preheat your oven to 350°F (175°C). Grease and line an 8×8 inch baking dish with parchment paper, leaving some overhang for easy removal.
• In a large bowl, cream together the softened butter and granulated sugar until light and fluffy.
• Add the eggs, one at a time, beating well after each addition.
• Mix in the lemon zest and lemon juice until well incorporated.
• In a separate bowl, whisk together the flour, baking powder, and salt.
• Gradually add the dry ingredients to the wet ingredients, mixing just until combined.
• Spread the batter evenly into the prepared baking dish.
• Bake for 20-25 minutes, or until a toothpick inserted into the centre comes out clean.
• Allow the brownies to cool completely in the baking dish on a wire rack.

For the Glaze:

• In a small bowl, whisk together the powdered sugar, lemon juice, and lemon zest until smooth.
• Once the brownies are completely cooled, spread the glaze evenly over the top.
• Allow the glaze to set before cutting into squares.