In a large bowl, combine the pancake mix, the milk, oil or melted butter, and one egg. Mix until there are no visible lumps, but don't overmix.
Let the batter rest for 2 minutes to thicken.
Cook the pancakes
Heat a large non-stick skillet or griddle over medium heat. Once hot, grease it with oil or butter. Pour ¼ cup of batter per pancake on the greased, hot skillet.
Cook the first side for about 2 minutes until the edges are defined and bubbles form. Flip and cook the other side for an additional minute.
Remove from the skillet and repeat with the remaining batter. Serve hot with butter and syrup.