Brown Sugar, Butter, Sugar, Flour, Eggs, Cocoa Powder, Oil, Baking Soda, Corn Starch, Corn Syrup, Salt and Vanilla.
Add the melted butter, white sugar, brown sugar, eggs, egg yolk, vanilla, oil and corn syrup to a mixing bowl. Stir to combine.
In a separate bowl, whisk together the cocoa powder, flour, cornstarch, baking soda, and salt.
Add the dry ingredients to the wet ingredients and stir until just combined. Do not over mix.
Line a 9x13 baking dish with parchment paper and spread the brownie batter to the edges. Bake at 350 degrees for 25 minutes then allow to cool.
Chocolate chips, whole milk, and butter.
Add the chocolate chips, butter, and milk to a medium saucepan and melt over medium heat, stirring constantly.
Once the chocolate has completely melted and the ganache is smooth, allow it to cool for 30 minutes before spreading over the top of the brownies.
Sprinkle with rainbow chips. Refrigerate the brownies for 30 minutes before cutting into bars and serving. Yum!