Preheat your oven to 350°F (175°C). Line a 9x13 inch baking pan with parchment paper, leaving an overhang on the sides to easily lift the blondies out later. Lightly grease the parchment paper.

In a large mixing bowl, melt the unsalted butter. Add the granulated sugar and light brown sugar to the melted butter and whisk until well combined and smooth.

Beat in the eggs one at a time, ensuring each is fully incorporated before adding the next. Stir in the vanilla extract and lemon zest until just combined.

In a separate medium bowl, whisk together the all-purpose flour, baking powder, and salt.

Gradually add the dry ingredients to the wet ingredients, mixing with a rubber spatula until just combined. Be careful not to overmix, as this can lead to tough blondies.

Gently fold in the finely diced fresh strawberries. Distribute them evenly throughout the batter.

Pour the batter into the prepared baking pan and spread it evenly with the spatula.

Bake for 25-30 minutes, or until the edges are lightly golden brown and a toothpick inserted into the center comes out with moist crumbs, but not wet batter. Do not overbake to keep them fudgy.

Remove the blondies from the oven and let them cool completely in the pan on a wire rack before attempting to lift them out or cut them. This allows them to set properly.

While the blondies cool, if using, prepare the lemon glaze: In a small bowl, whisk together the powdered sugar and fresh lemon juice until smooth. If the glaze is too thick, add milk or water 1 teaspoon at a time until it reaches your desired drizzling consistency.

Once the blondies are completely cool, drizzle the lemon glaze over the top. Let the glaze set for about 15-20 minutes before cutting into squares.

Lift the blondies from the pan using the parchment paper overhang and cut into 24 squares. Serve and enjoy!