Preheat oven to 350 degrees F. In a large mixing bowl, use an electric mixer to cream the butter. Add the brown sugar and 1/2 cup sugar and cream together. Beat in the peanut butter, then add the eggs one at a time, mixing until combined. Mix in the vanilla extract.

In a small mixing bowl, sift together the flour, baking soda, baking powder and salt. Add dry ingredients to the creamed mixture and mix well.

Pour the remaining 1/4 cup sugar in a small bowl. Take a heaping tablespoon of dough and form into a ball. Coat the ball in sugar by rolling it around in the bowl. Place on an ungreased cookie sheet about 2 inches apart.

Press the tines of a fork into the balls to create the cross-cross pattern on the top and to flatten the dough a titch. Bake for 10 to 12 minutes or until cookies are set and lightly brown around the bottom edges.