Stir the 1/2 cup sugar and 1 tablespoon cinnamon together in a shallow dish for the coating. Keep the 4 tablespoons of melted butter nearby with a pastry brush.
Whisk together the flour, sugar, baking powder, baking soda, cinnamon, and salt in a large bowl.
Whisk the buttermilk, melted butter, and vanilla, then stir into the dry ingredients just until combined. Rest the batter 5 minutes.
Cook 1/4 cup portions on a greased griddle over medium heat until bubbles form, then flip and cook until golden on both sides.
Heat the cream until steaming, about 45 seconds in the microwave, and pour it over the chocolate chips. Let sit 1 minute, then stir until smooth and glossy.
While the pancakes are still warm, brush both sides with melted butter and press into the cinnamon sugar until fully coated.
Stack and serve with the warm chocolate sauce for dipping or drizzling, just like fresh churros at a fair.
