This is a Brownie or Blonde Brownie or Bar cookie
I don't remember which, but it is a very old receipe (around the middle to late 1950s). I know brown sugar,butter (all the usual) ingredients for brownies, but the receipe called for chocolate chips that you put over the top of the batter. then you put it in the oven for 1 minute then take it out, run a knife through it to swirl then immediately return to oven to finish baking. it was important to not overback. Do not confuse with the cream cheese swirl brownie because cream cheese is not one of the ingredients. I hope someone can come up with the receipe because I have searched all over
the web and it is a wonderful delicious receipe.