In a large bowl, whisk together flour, sugar, cocoa powder, baking powder, and salt.
Pour mixture into a pint-sized mason jar (or container of your choice), or if using chocolate chips pour into 1 ½ pint-sized jars, tamp down with a spoon, and then fill to the brim with chocolate chips. Cover and attach a tag with the following instructions:
Instructions for Baking Brownie Mix
Preheat oven to 350F.
Pour brownie mix in bowl and add melted butter, eggs, and vanilla.
Stir very well and spread into a lightly greased 8x8” or 9x9” pan.
Bake for 25-30 minutes in 8x8” pan or 23-25 minutes for 9x9”.
A mason jar makes a cute way to hold the brownie mix and it is a great option to store it, but if you're just making this for yourself you can store in any container that it fits in, even a Ziploc bag.