Preheat oven to 350°F (175°C). Grease a 9x9 inch baking pan or line it with parchment paper.
In a medium bowl, whisk together flour, cocoa powder, baking powder, and salt.
In a larger bowl, whisk melted butter and sugar until smooth and glossy.
Add eggs one at a time, whisking well after each. Stir in vanilla extract.
Slowly pour in the red wine and whisk until smooth.
Fold in the dry ingredients gently, just until combined.
Stir in the chocolate chips (and any optional add-ins).
Spread the batter evenly into the prepared pan.
Bake for 30–35 minutes, until a toothpick inserted in the center comes out with a few moist crumbs.
Let brownies cool completely before cutting into squares.
