Preheat oven to 350°F. Grease an 8x8 inch baking pan.
In a medium bowl, whisk together the melted butter and sugar until combined.
Beat in the eggs one at a time, then stir in the lemon juice and zest.
Fold in the flour and salt until just combined, being careful not to overmix.
Pour the batter into the prepared baking pan and spread it out evenly.
Bake for 20-25 minutes, until a toothpick inserted in the center comes out clean.
Allow the brownies to cool completely in the pan before cutting into squares.
