These things are evil!!! I can feel my pants getting tighter! I used half oil & half butter, because I recently saw on America's Test Kitchens that oil helps to make a chewier brownie. I minimally swirl them, so I get distinct flavors of pumpkin & chocolate. Did I mention these things are evil?! Next time I am going to sprinkle some chocolate chips & nuts on the top. I have to go and eat another one.