Isnt this awesome!? i was so happy with this turnout that i had to cut open atleast 5 or 6 cupcakes to see if they all did it, and they did. these are done with chocolate chip oatmeal cookie dough. i have tried it with peanut butter and sugar cookie and peanut butter with reeces pieces in it. they all do this , but not as much. but the flavor of the other cookie does taste good with the brownie, especially the peanut butter. its not a strong taste but its still there.