Holding the glass at a 45-degree angle with one hand, pour the chocolate syrup down the sides of the glass. Let the chocolate syrup touch the glass near the mouth then slowly turn the glass around so that you have chocolate syrup running down the glass from every angle.
Pour in the sweetened condensed milk, hot coffee and evaporated milk. I did it in that order but the order is entirely interchangeable.
Spoon the lightly whipped cream on top of the drink.
Optionally, sprinkle with dark chocolate bits before stirring and enjoying your tres leches coffee.