Heat oven to 350°F
Make brownies as directed.
Add in 1/2 cup chocolate chips - mix well.
Add 6 graham crackers to 13x9 pan
Top with brownie batter and bake as directed.
After removing pan from oven, set oven to broil.
Immediately sprinkle marshmallows and graham crackers over warm brownies.
Broil about 4 to 5 inches from heat 30 to 60 seconds or until marshmallows are golden brown. (Watch carefully marshmallows and graham crackers will brown quickly.)
Sprinkle with chocolate chips.
To serve warm, cool about 30 minutes.