Whisk together the flour, sugar, baking powder, baking soda, and kosher salt and set aside. Add the buttermilk and the eggs, whisk to combine, and then add the butter and vanilla. Whisk once more and then allow the batter to rest while the griddle or pan heats.
Be careful not to overbeat the pancake batter, lumps are fine. This is a thick batter and the pancakes will thin out as they cook on the griddle. Stir in the pecans.
Heat a flat-bottom nonstick skillet or electric griddle (this is my favorite griddle) over medium heat. Pour about ⅓ cup of batter onto the griddle for each pancake.
Allow the pancakes to cook until they begin to bubble on top and are lightly browned on the bottom, about 2-3 minutes. Flip and cook the second side until golden brown. Serve warm with the toppings of your choice.
Notes
While regular milk may be substituted for the buttermilk in this recipe, I strongly recommend making the recipe as written. (If you do choose to substitute regular milk, reduce the amount to a total of 2 cups.)