01 - In a large mixing bowl, whisk together the flour, sugar, baking powder, baking soda, salt, and ground cinnamon until evenly combined.
02 - In a separate bowl, whisk the milk, eggs, melted butter, and vanilla extract until fully blended and smooth.
03 - Pour the wet ingredients into the dry mixture. Gently fold together until just combined; small lumps are acceptable. Allow the batter to rest for 5 minutes to thicken slightly.
04 - Preheat a non-stick skillet or griddle over medium heat. Lightly grease the surface with a small amount of butter.
05 - Pour approximately 1/4 cup of batter per pancake onto the heated griddle. Cook until bubbles form across the surface and edges appear set, about 2-3 minutes. Flip and cook for an additional 2-3 minutes until golden brown on both sides.
06 - While pancakes cook, combine the 1/4 cup sugar and 2 tsp cinnamon in a small bowl. Mix thoroughly to create an even coating mixture.
07 - Place the chopped dark chocolate and heavy cream in a microwave-safe bowl. Microwave in 20-second intervals, stirring between each, until the chocolate is completely melted and the sauce is smooth and glossy.
08 - While pancakes are still warm, lightly brush the surface with melted butter if desired, then generously dust both sides with the cinnamon sugar mixture. Stack pancakes and drizzle with warm chocolate sauce or serve sauce on the side for dipping.