1Preheat oven to 350°F.
2Spoon 24 rounded tablespoonfuls dough 2 inches apart on ungreased cookie sheets. Bake 11 to 13 minutes or until golden brown. Cool 10 minutes while making the filling.
3In mixer bowl, beat peanut butter, butter and powdered sugar together. Add marshmallow cream, vanilla bean and vanilla extract to the butter mixture. Add a tablespoon or 2 of water if it gets too thick. Mix well, and set aside.
4Set up an assembly line, and lay out 12 cookies, bottom sides up. Spoon or pipe filling with a pastry bag evenly on each cookie. Sandwich each cookie with another cookie until you have 12 whoopie pies or cookie sandwiches. Serve immediately, or store in airtight container.