2 pound bags of mushroom popcorn - this larger popcorn variety pops up in a ball and is a favorite of those that enjoy making caramel corn or different flavors for fun snacks and desserts. Disclaimer: when mushroom popcorn is popped over low/medium heat, the result is very few "mushroom shaped kernels. When the corn is popped with intense high heat, the "mushroom" shaped kernels appeared. We have seen this modification result in much higher popping percentages and better mushroom popcorn. There will always be a certain small percentage of mushroom kernels that pop up in the standard butterfly fashion. It really all depends on the composition of the popcorn kernel. We have no way of 100% ensuring that the entire batch will pop up in a ball. This cannot truly be done until the popcorn is already popped and sorted.