Crush all graham crackers into large chunks. Around the size of a quarter works best.
Microwave marshmallows and butter together in a large bowl for about two minutes, stopping to stir after one and a half minutes. Marshmallows should still be a little fluffy, but fully combined with the butter.
Add graham crackers to marshmallows and mix until crackers are well coated.
Place mixture in a large dish and spread evenly.
Microwave chocolate chips for 60 seconds, stopping after 30 seconds to check and stir. If still not melted, microwave in 15 second increments until melted.