Grease or line an 8x8 baking dish with parchment paper.
In a medium bowl, whisk together the eggs, melted butter, vanilla extract, and milk until smooth.
Stir in the homemade brownie mix until fully combined. Do not overmix—just stir until no dry streaks remain.
Pour the batter into your prepared baking dish and spread evenly.
Bake for 20–25 minutes, or until a toothpick inserted in the center comes out with a few moist crumbs. If you add chocolate chips, nuts, or other mix-ins, you may need to bake for a couple of extra minutes to ensure the center is set.
Allow brownies to cool before cutting for clean edges (if you can wait!).
Notes
Recipe Tips & Tricks
Don’t Overmix the Batter: Once you add the homemade brownie mix to your wet ingredients, stir just until combined. Overmixing can make brownies dense and tough, rather than soft and fudgy.
Slightly Underbake for Fudgy Centers: For that rich, fudgy texture, pull the brownies out when a toothpick comes out with a few moist crumbs (not wet batter). They’ll continue to set as they cool.
Use Melted Butter (Not Cold): Make sure your butter is melted and slightly cooled before mixing. This helps create a smooth batter and gives brownies that classic, rich, chewy texture
Pro Tip: If you add chocolate chips, nuts, or other mix-ins, you may need to bake for a couple of extra minutes to ensure the center is set. For best results, use about 1/2 cup of chocolate chips, 1/2 cup of chopped nuts, or 1/4 cup of peanut butter swirled into the batter. This adds just the right amount of flavor and texture without overwhelming your brownies.