In a small bowl, mix together the flour, cocoa powder, and baking soda. In a large bowl, beat together the sugars, butter, and 1/4 cup of peanut butter until light and fluffy. Beat in vanilla and egg. Slowly mix in the flour mixture. Set aside.
For the peanut butter filling, combine confectioners’ sugar and 3/4 cup peanut butter. Beat together well. Roll filling into 30 small balls. Try to keep the balls all the same size—around 1 inch.
For each cookie, use 1 tablespoon of chocolate dough and roll into a ball. It helps to flour your hands first. Squish the ball of chocolate dough flat and place a peanut butter ball in the center. Wrap the chocolate dough up and around the peanut butter ball to completely cover. Place 2 inches apart on a baking sheet. Dip the bottom of a glass into white sugar and use the cup to lightly flatten the cookie balls. Bake for 7-9 minutes.