Mix flour, baking powder, salt, and sugar in a large bowl (if you made the mix ahead, just use one bag of the dry mix)
In another bowl, whisk together the milk, egg, butter, and vanilla.
Add wet to dry, and whisk until a smooth batter forms.
Heat a skillet over medium heat, and grease lightly with butter.
Pour ¼ cup batter into circles.
Flip once bubbles appear and sides are lightly golden.