Melt the chocolate in 15-second bursts in the microwave. Allow it to cool a bit.Sift the cocoa powder and flour together in a bowl. Salt and baking powder should be added.
1
Beat butter, brown sugar, and sugar on high for 2 minutes with a mixer. Mix in melted chocolate. Beat high for 1 minute. Mix in vanilla, eggs, and yolk. Beat high for 1 minute. It will be airy.
2
Putting in the dry stuff. Mix slowly until everything is just mixed. Warm the oven up to 350°F. Put parchment paper on two cookie sheets. Put the dough in the fridge for 20 minutes.
3
Take a 3oz cookie scoop. Scoop dough and bake 6 cookies per sheet. Bake 13-15 minutes.Wait 5 minutes before chilling the cookies on a rack. Cool fully.
4
Start ganache while cookies cool in fridge. Medium-low heat the heavy cream in a sauce pan. Heat till steaming. Cover chocolate chips with heated cream.
5
Let it sit 2 minutes. Stir smooth. Melt any remaining chocolate bits in the microwave for 10 seconds.Hold the ganache until all cookies are done and cooled.
6
When the final batch of cookies bakes, chill the chocolate for 20 minutes. Cover cookies with chocolate. Put chocolate rainbow candy on top.
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