Beat butter and shortening at medium speed with an electric mixer until creamy.

Gradually add sugar, beating well.

Add eggs and milk, beating until blended.

Combine flour, baking powder, baking soda, and salt in a separate bowl.

Add the dry ingredients to the butter mixture, beating at low speed just until blended.

Stir in lemon rind and juice.

Divide the dough into 4 equal portions.

Wrap each portion in plastic wrap.

Chill for at least 2 hours or up to 6 hours.

Roll out one portion of dough to a 1/4-inch thickness on a lightly floured surface.

Cut out heart shapes using a 3-inch cookie cutter.

Place cookies on lightly greased baking sheets.

Repeat with remaining dough portions.

Bake at 350°F for 8-9 minutes or until lightly browned on the bottoms.

Let cool on baking sheets for 2 minutes.

Remove to wire racks and cool completely (about 20 minutes).

Remove and reserve about 1/4 cup of icing.

Tint the remaining icing with green food coloring.

Spread green icing on the tops of the cookies.

Tint the reserved 1/4 cup of icing with orange food coloring.

Spoon the orange icing into a zip-top plastic bag.

Snip one corner to make a small hole.

Pipe dots on the cookies.