From the 1785 Inn and Restaurant, Intervale, NH.
Pop the popcorn (we use an air popper) and place it in a large bowl, removing any unpopped kernels. Melt the butter and marshmallows in a saucepan over low heat until melted and smooth. Add the salt and stir. Pour the mixture over the popcorn and stir until the popcorn is evenly coated. Form into approximately 15 balls.