The sugar within caramelises on the outside creating the scorched outer crust which imparts an incredible caramelised, créme brûlèe-esque flavour. Let the parchment stick up at least 2 inches (5 cm) above the sides https://www.google.com/maps/d/u/0/viewer?mid=1f-w0Y0Vx_ujuRWDNFP0eG8oK_v2ZFWM&ll=39.864387271712886%2C32.652109310000014&z=12