With an electric mixer cream butter with sugar until light and fluffy. Beat in egg and essence.Add sifted flour and baking powder to butter mixture 1 cup at a time, mixing after each addition. Divide dough into balls.
On a floured surface,roll each ball into a circle about 1/8 in. thick.
Dip heart-shaped cookie cutter in flour before each use. Cut out the cookies. Roll the dough left after cutting out cookies into a ball again and use as above.
Bake cookies on ungreased cookie sheet 6-7 minutes or until cookies are lightly browned.
Notes
For a fancier presentation, you can decorate the cookies with icing, and/or colored sugar.