Preheat griddle 350°F or heat frying pan over medium heat until a fleck of water “dances” in the pan.
If using milk, add vinegar or lemon juice to the milk and let it sit while you whisk the dry ingredients.
Whisk flour, sugar, salt, baking powder, and baking soda.
Add egg, buttermilk, and oil. Whisk until combined (batter may be slightly lumpy). Cook pancakes immediately so the bubbles created by the baking soda don't dissipate.
You'll know your pan is hot when the water dances: flick a bit of water on the pan. If it dances around (i.e. boils), your pan is ready. If it sits, let it heat up a bit longer.
Cook pancakes, flipping halfway, on griddle or in pan greased with cooking spray. You know they're ready to flip when the bubbles form on the top and start to pop and the bottom is golden. Serve warm with syrup.
Freeze between paper towels in a ziploc bag for up to one month. Reheat in the microwave.