Preheat your oven to 350°F (175°C) and grease a 9x13-inch baking pan.
In a large mixing bowl, combine the melted butter and sugar, stirring until well blended.
Add the eggs one at a time, mixing well after each addition, then stir in the vanilla extract.
In a separate bowl, whisk together the flour, cocoa powder, and salt.
Gradually add the dry ingredients to the wet mixture, stirring until just combined.
Gently fold in the chopped strawberries and chocolate chips if using.
Pour the brownie batter into the prepared baking pan, spreading it evenly.
Bake for 25-30 minutes, or until a toothpick inserted into the center comes out with a few moist crumbs.
Allow the brownies to cool in the pan for at least 15 minutes before cutting into squares.