In a large mixer bowl, cream together the peanut butter and unsalted butter until fluffy. At low speed, mix in the egg, pureed banana, SugarTwin® Granulated Brown, SugarTwin® Granulated White, and vanilla.
With the mixer at low speed, slowly add the sifted dry ingredients until fully mixed.
Shape dough into one-inch balls. Place on ungreased cookie sheet 1” (2.5cm) apart. Flatten cookies with the palm of your hand.
If desired, make a fruit topping by mixing preserves with SugarTwin® Granulated White. With your thumb, make an indent in the middle of each cookie and fill with 1/4 tsp (1.25mL) of the fruit topping.
Bake for 12 – 14 minutes or until bottoms are golden brown. Remove cookies from cookie sheets to wire rack, and cool completely.