If you are using buttermilk, the first step is to make the buttermilk. In a small mixing bowl, add milk and vinegar, stir, and let sit for two minutes. (You can also use regular milk for this recipe instead of buttermilk, but we love it with buttermilk).
In a medium mixing bowl, add flour, sugar, baking powder, baking soda, and salt. Whisk dry ingredients until evenly combined.
Next, add the egg, milk, vanilla extract, and melted butter into the dry ingredients and whisk until just combined. Do not over-mix as it will change the texture. Lumps are ok.
Over medium heat, place a non-stick pan or griddle and lightly grease with a pad of butter.
Using a ladle or measuring cup, pour 1/3 cup scoops of pancake batter onto your hot pan. Arrange a handful of blueberries on top of the batter. Cook for about 1-2 minutes until you start to see bubbles form on the surface and the bottom is golden brown. Flip your pancake using a spatula and cook the opposite side for another 1-2 minutes until golden brown on both sides.
Serve immediately with your favorite pancake toppings. Maple syrup, powdered sugar, butter, whipped cream, and/or fresh berries are all great options.