Preheat the oven to 400 degrees F (200 degrees C).
Beat butter and sugar in a large bowl with an electric mixer until light and fluffy. Mix in almonds, egg, and amaretto. Gradually add flour until well blended. Drop spoonfuls of dough 2 inches apart onto ungreased cookie sheets.
Bake in the preheated oven until cookies are lightly browned, 5 to 8 minutes.
