Line a sheet tray with parchment paper.

In a large bowl mix together the brown mix, oil, and egg until combined, the mixture will be thick. Take 2 tablespoons of cookie dough and roll it into a ball, place it on the sheet tray, repeat with the remaining dough. Place the sheet tray into the fridge for 30 minutes to chill.

Preheat the oven to 350°F. Line sheet trays with parchment paper.

Place the chilled cookie dough 2-3 inches apart onto the sheet trays. Bake for 9-11 minutes until the tops of the cookies no longer look glossy, do not overbake.

Let cool for 10 minutes on the sheet tray and transfer to a wire rack to cool completely.

When the cookies are cool, make the ganache. Finely chop the baking bar and place it in a heat-proof bowl, set aside.

Place the heavy cream into a small saucepan and bring it just to a simmer. Pour the hot cream over the chocolate. Let it sit for 5 minutes. Whisk until smooth.

Take the cookies one at a time and dip the tops into the ganache. Place it back on the wire rack ganache side up and immediately top with the rainbow candy chip sprinkles. Repeat with the remaining cookies.