In a large bowl, whisk together the flour, sugar, baking powder, baking soda, and salt.
In another bowl, whisk the buttermilk, egg, melted butter, and vanilla.
Pour the wet ingredients into the dry ingredients and stir gently until just combined. A few lumps are totally fine—don’t overmix!
Gently fold in the blueberries.
Heat a nonstick skillet or griddle over medium heat and brush with a little butter. Pour 1/4 cup batter for each pancake. Cook until bubbles form on the surface and the edges look set, about 2 minutes. Flip and cook another 1–2 minutes until golden brown.
Stack them up and top with more blueberries, a pat of butter, and a drizzle of maple syrup.