Preheat oven to 350°. In a large bowl, combine cake mixes, eggs and oil; beat until well blended. Shape into 1-in. balls; place 2 in. apart on greased baking sheets. Flatten with bottom of a glass dipped in granulated sugar.
Bake 7-9 minutes or until tops are cracked. Cool 2 minutes before removing to wire racks to cool completely.
In a large bowl, beat cream cheese, butter and extract until blended. Gradually beat in confectioners' sugar until smooth.
Spread filling on bottoms of half of the cookies; cover with remaining cookies. Refrigerate leftovers in an airtight container.