Beat the butter, powdered sugar, and vanilla extract together with a spoon. Then, stir in the flour.
Once just combined, roll out the dough on a floured surface. Once it is in a ½ inch thick sheet, use a cookie cutter to create an even number of cookies.
Place the cookies on an ungreased cookie sheet, then bake for about 15 minutes or until set and bottoms are light golden brown. Immediately remove from cookie sheet to wire rack. Cool completely, about 30 minutes.
Once cooled, flip half of the cookies over. Spread a small dollop of cool whip on each, then lay sliced fruit over top. Add another dollop of cool whip and top with another shortbread cookie.