Melt butter in a large pot over medium-low heat. Add marshmallows and stir until completely melted. Reduce heat to low and stir in Lucky Charms cereal.
Remove pot from heat. Using a medium cookie scoop, scoop mixture and roll into individual balls, placing on non-stick baking sheet.
Allow to set at room temperature for 30 minutes to 1 hour. Store in an airtight container for up to 4 days.
Recipe by Mom to Mom Nutrition at https://momtomomnutrition.com/food-and-recipes/lucky-charms-bites/