Your Pan (any loaf, square, or rectangular pan works)
Two all-metal binder clips
1batch of batter
Cut parchment to size: cut the parchment to the proper width for your pan. This is the longer dimension of your pan, so 13" for a 9" x 13" pan, 9" for a 9" x 5" pan and so on. The length should be long enough to contact and cover the inner sides and the bottom of your pan, with at least a 1" overhang out the top of each side (see video for a visual example).
Grease your pan: grease the bottom of your pan with baking spray, a little butter, or a few drops of vegetable oil.
Smooth the parchment: center your parchment strip over your pan, and press it into the bottom of the pan to adhere and remove big air bubbles. Start by pressing the parchment to contact the pan in the center, and then work your way towards the edges to push the air bubbles out through the corners.
Crease at the edges: loosely crease the parchment along the bottom corner edges and over the top edges of your pan.
Clip the overhang down: make sure the parchment is fully in contact with the bottom and side walls of the pan (no air gap below the paper in the bottom corners), then clip the excess overhang onto each side of the pan. (This secures the parchments edges, so they don't flop into your batter during the bake and ruin all your hard work!)
Remove with the sling: once your loaf/bars are ready to un-pan, use an offset spatula or thin knife to gently release the loaf from the ends of the pan. Then remove the clips, grab the two parchment flaps that hang over the edges of the pan, and simple pull directly up on the parchment sling while gently pushing straight down on the pan (see notes). Et voilà - a perfect release every time!
IMPORTANT NOTE! Make sure your product is fully cooled before removing it with the parchment sling. And please note, some delicate products may not lift as a single piece well and will still be best cut right in their pan. In these cases though, the parchment lining will still be a big help when it comes to making sure your product releases once cut.