How to Make It
Heat a large nonstick skillet or griddle over medium. Whisk together flour, sugar, baking powder, and salt in a large bowl. Whisk together milk, peanut butter, butter, egg, and egg yolk in a bowl until smooth. Add milk mixture to flour mixture; stir until smooth. Stir in chocolate chips.
Brush skillet with a little melted butter. Working in batches, spoon batter by ¼-cupfuls into hot skillet. When tops of pancakes are covered with bubbles and edges are dry, turn pancakes. Cook until just cooked through, about 1 minute. Top pancakes evenly with whipped cream and chocolate sauce if using.