Preheat the oven to 350 degrees. Cream the butter and sugar together until fluffy. Stir in the vanilla. Add the flour slowly, mixing well after each addition. Roll the dough out onto a floured surface and cut into circles with a cookie cutter. I used a 3-inch circle. Bake for about 20 minutes, depending on the size of your circles, until the edges are just golden brown. Allow to cool on the pan for about 5 minutes before transferring the cookies to a cooling rack. Let the cookies cool completely. Place about 1 tablespoon, depending on the size of your cookie, of the frosting on top of the cookie and sprinkle with the chopped pecans. Serve and enjoy!