In a medium sauce over medium heat, combine milk, water, and sugar and whisk until sugar is dissolved. Whisk in cocoa powder, vanilla, and a pinch of salt. Stir until well blended and heat until it reaches desired drinking temperature.
Divide into oven safe serving mugs, and top with marshmallows. Place under the 'low' setting broiler for 1-2 minutes, leaving the oven cracked and watching constantly. Remove once golden brown, they will turn to burning very quickly, just like a bonfire!
Top with a drizzle of chocolate sauce or hot fudge and crushed graham crackers.
I make mine with unsweetened almond milk, super good! Works great with dairy or dairy free milk!