• Preheat the oven to 350°F. Grease a 9x9-inch metal baking pan and line it with parchment paper, leaving an overhang to easily lift out the brownies once baked.
• Place the chocolate chips and butter in a medium microwave-safe bowl. Microwave on medium power for 1 minute, then stir to combine. Continue microwaving in 30-second intervals, stirring after each, until melted and smooth.
• Transfer the chocolate mixture to a large bowl and whisk in the granulated sugar and brown sugar until combined. Add the eggs and whisk until well incorporated. Stir in the vinegar, vanilla extract, and red food coloring until combined. Add the flour, cocoa powder, and salt, and mix until smooth.
• Pour the batter into the prepared pan and bake for 25–30 minutes, or until a toothpick inserted in the center comes out with just a few moist crumbs. Remove the brownies from the oven and let cool for 10 minutes before transferring to the refrigerator to finish cooling.

Cream Cheese Frosting

• In a large mixing bowl, beat the cream cheese and butter on medium speed until smooth and well combined, scraping down the sides of the bowl as needed.
• Add the remaining ingredients and mix on low speed until combined. Scrape down the sides of the bowl, then increase the speed to medium-high and beat until the frosting is light and fluffy.
• Once the brownies have cooled, spread the cream cheese frosting evenly over the top. Refrigerate until the frosting is firm.