Beat cream cheese and butter at medium speed of an electric mixer until creamy. Gradually add flour and cinnamon, beating at low speed just until ingredients are blended. Wrap dough in wax paper, and chill 2 hours.
Divide dough in half. Divide each half of dough into 12 balls. Place in lightly greased miniature (1 3/4-inch) muffin pans, shaping each into a shell.