Preheat the oven to 170°C.
In a bowl, mix peanut butter, sugar, and egg together.
Sift in flour and baking powder, then mix until well combined.
Scoop the dough by spoonfuls, shape into balls, and place on a baking sheet.
Top each dough ball with peanuts for decoration.
Bake in the 170°C oven for 12-15 minutes, then let cool.