In the bowl of a standing mixer fitted with the paddle attachment or a large mixing bowl, cream together the butter and sugar on medium speed, until just combined. Beat in the almond extract and salt. With the mixer running on low, slowly add in the flour, mixing just until the dough begins to come together. Transfer to a lightly floured surface, then press and roll into a flat disk. Wrap with plastic and place in the refrigerator to chill for 30 minutes.