Warm a nonstick skillet or griddle over medium heat and lightly grease with oil.
Whisk flour, sugar, baking powder, baking soda, and salt in a large bowl.
In a separate bowl, whisk buttermilk, egg, and vanilla. Slowly whisk in the melted butter.
Pour the wet mixture into the dry ingredients and stir just until a few streaks of flour remain.
Fold in the sprinkles gently to keep colors from bleeding.
Scoop about 1/4 cup batter per pancake onto the hot surface. Cook until edges set and bubbles form, 2–3 minutes.
Flip and cook until golden and cooked through, 1–2 minutes more. Repeat with remaining batter.
Serve warm with maple syrup and extra sprinkles if you like.