In a large bowl, mix together the buckwheat flour, brown sugar (if using, if using maple syrup, save for a later step), cocoa powder, baking powder, baking soda, and salt. Set aside after thoroughly combining.
In a medium bow, add the maple syrup if using, egg, vanilla, buttermilk, and oil together and mix until well combined.
Mix the wet ingredients into the dry ingredients and stir until just combined. Allow to sit for about 5 minutes.
Fold in the chocolate.
Add ¼ cup of the batter into the skillet. Cook for about 2 - 3 minutes or until the top starts bubbling and the bubbles begin to pop. Flip, and cook for about another 1 - 2 minutes. Repeat with the remaining batter.
Notes
*I used a mix of natural cocoa powder and dark cocoa powder