I usually use a hangman's knot for my paracord, but I was using it last night to tie up a box in an pinch and realized it wasn't the easiest to untie. I though I would ask if someone has a better knot and can give me a link

I think you're looking for something like a "chain knot". Give the end a pull and it unzips very easily. I use it on long lengths to prevent tangling. In this case double or quadruple the rope first to make it go faster.