Bring to a boil and cook on high for 2 minutes, stirring constantly.
Add soda and quickly stir as it foams.
Pour over the popped corn in a brown bag and shake the bag.
Roll top of bag closed and place in microwave. Cook for 90 seconds.
Shake bag and cook for another 90 seconds.
Shake and cook for 60 seconds.
Pour and spread out onto a cookie sheet.
Once cool, break apart and store in a sealed bag or container.