Off the Bryn Mawr stop on the far North Side of Chicago, there was a little storefront called "Barry's Pizza Spot". They sold stuffed pizza^*^ by the slice, and they almost always had one that sausage, mushroom, and onion. I sublet an apartment off this stop for a month one summer and ate this slice for dinner over a dozen times. The first time, it was the best pizza of my life. Two other times surpassed the record before I moved away. It closed a couple years later. My mouth is watering just thinking about it now.

^*^If you don't know what stuffed pizza is, it's the best of the three Chicago pizza styles. It's stopped pretending to be anything other than a pie, and the cheese and "toppings" are all underneath a second, upper crust that's prevented from burning by a top layer of sauce. One slice is a meal.