Spray cooking spray on a square baking pan that is 8 x 8 or 9 x 9. Put away.
Step 1
Heat a big pot on medium. Add butter and melt. Add sweetened condensed milk and simmer for 1-2 minutes until bubbling. Mix in salt and vanilla.
Step 2
Lower the heat and melt 6 cups of marshmallows, stirring constantly and scraping the pan.
Step 3
Stir in Lucky Charms and the last cup of mini mallows after removing from heat. Mix thoroughly to coat.
Step 4
Place in preheated pan immediately. Spray your hands with cooking spray to properly distribute the ingredients. Avoid patting! Cool before slicing and serving.