Combine milk with the vinegar, and let sit for 5 mins.

In a small bowl, whisk together flour, powdered sugar, baking powder, baking soda, and salt: set aside

In a medium bowl, whisk together milk & vinegar, vanilla, butter, and egg. Add dry ingredients to milk mixture; whisk until just moistened (do not overmix; a few small lumps are fine).

Heat a large skillet (nonstick or cast-iron) or griddle over medium. Fold a sheet of paper towel in half, and moisten with oil; carefully rub skillet.