In a large bowl, sift together the flour, baking powder, salt, and sugar.
Make a well in the middle and pour in the milk, egg, and butter. Break up the egg first with a fork, and then begin to combine the flour, working from the outside of the bowl in, until just combined and mostly smooth. If the batter is too thick, read the note below.
Cook the pancakes:
Heat a non-stick griddle or large pan over medium heat. Once hot, grease, spray, or melt butter on the hot surface. Immediately, pour ¼ cup of batter per pancake. Cook the first side for 2 minutes, looking out for the edges to be defined and bubbles to form. Flip the pancakes over and cook for almost 2 more minutes on the other side. Remove from the pan onto a plate and keep them warm while you cook the rest of the batter.
Plate a few pancakes on a plate and top them with your favorite toppings and syrups.
Notes
Some eggnogs are thicker than others (this depends on the brand and fat content, dairy or non-dairy). If the batter is too thick, add 2 tablespoons to thin it out, but no more than ¼ cup if using full-fat eggnog.