Whisk together the flour, sugar, baking powder, baking soda and salt in a large bowl.
In another bowl whisk together the buttermilk, milk, eggs and vanilla.
Add the buttermilk mixture to the flour mixture and whisk until completely incorporated.
Whisk in the melted butter.
Heat a griddle, Griddler, or large skillet over medium heat. Spray with non-stick spray (or melt 1/2 tablespoon of butter).
Working in batches, spoon 1 heaping tablespoon of batter onto the griddle. Do not crowd the pancakes. I was able to cook 12 at a time on the Cuisinart Griddler.
Once the tops of the pancakes start to bubble (2-3 minutes on the Griddler, maybe sooner on a stove-top), flip and continue to cook until browned, another 30 seconds or longer.
Keep cooked pancakes in a warmed oven until all of the batter is used.