Place popcorn in a large bowl and make sure to take out all of the unpopped kernels.
In a large microwave safe bowl, heat marshmallows and butter for 1 minute on medium power. Stir to combine. Heat in additional 30 seconds increments until fully melted and smooth.
Add food coloring to marshmallow mixture and stir to combine. Pour over popcorn and add candies. Stir to coat as completely as possible. Serve right away.
Notes
*If fruity conversation hearts aren't your thing, use your favorite candies (such as M&Ms)
Recipe by Crumbs and Chaos at http://www.crumbsandchaos.dreamhosters.com/2015/01/gooey-marshmallow-popcorn-party-popcorn-giveaway/