Preheat oven to 350°F.
Cream butter and sugar. Blend in flour and nuts to form stiff dough.
Divide dough into two gallon-sized plastic food storage bags, roll to ¼-inch thickness then chill.
Cut bag at seams and uncover top of dough. Cut dough with 2-inch heart-shaped cutter. Then use an apple corer or smaller heart-shaped cutter to remove the centers from half of the hearts. Dough scrapes can be reformed and placed within the cut bag for re-rolling (chill if necessary.)
Place cookies on ungreased cookie sheet. Bake 10-12 minutes or until edges are slightly browned.
Allow cookies to cool. Spread jam on the bottoms of the whole cookies and sift powdered sugar over tops cookies with cutouts.
Place cutout cookies over jam spread cookie so jam shows through cutout.
Store in air tight container.