
Set one cup of the mini marshmallows aside.
Melt the butter, chocolate chips, mini marshmallows, and vanilla in a large pot over medium heat until mostly smooth.
Mix in the Golden Grahams cereal and remaining marshmallows. Stir to combine.
Press into a 9×13 pan. Let them cool / solidify for an hour or two. Cut into 12 big bars and devour like a hungry Golden Grahams Bar wolf.