Grease a 9x13 pan with butter; set aside.
Pour Golden Grahams into a large bowl. Pour 1 cup marshmallows right over top.
In a microwave safe bowl, place remaining 6 cups marshmallows and chocolate chips. Stir together and add margarine and corn syrup on top. Microwave for 45 seconds, stir, another 45 seconds, and stir again till it's nice and creamy. Then add vanilla and stir
Pour chocolate mixture over Golden Grahams mixture. Mix together and press into the greased 9x13 pan. Cover with plastic wrap and place in the fridge to firm.