01 - 
                Set your grill to low heat, about 300-325°F. For charcoal, make sure the coals are nearly gone and keep the heat on one side.
              
              
              
                02 - 
                Slice the bread rolls lengthwise so tops and bottoms stay together. Place them on a foil-covered tray or pan.
              
              
              
                03 - 
                Spread 2/3 of the chocolate chips on the bottom layer, add marshmallows, then the rest of the chocolate chips.
              
              
              
                04 - 
                Place the foil pan on the grill, close the lid, and let it cook for 4-10 minutes. Watch for melted chocolate and soft marshmallows.
              
              
              
                05 - 
                Put the top buns back on. Brush the tops with melted butter, sprinkle graham cracker pieces and sea salt if you like. Serve while warm.