Begin the pancakes by sifting together the flour, baking powder, salt and sugar into a large mixing bowl.
In a second bowl, beat together the egg, milk, and yogurt/sour cream. Then, stir this mixture into the flour mixture. Mix just until no flour streaks remain. Stir in the melted butter, and then the chocolate chips.
Heat a nonstick skillet or griddle, and melt a teaspoon of butter. Depending on what size you want your pancakes, ladle the correct amount of batter onto the skillet. When bubbles appear, flip your pancakes. Add more butter, as necessary.
Top the pancakes with maple syrup and whipped cream.