Knead five minutes, or until smooth. Cover and let rest five minutes. Spread filling over dough within half inch of edges. Starting with 18 inch side, roll up tightly, pressing edges to seal. Place seam side down on prepared baking sheet.
Join ends to form ring, placing prepared custard cup bottom side up in center of ring.
Pinch ends of dough to seal. Turn two cut sections on their sides in opposite directions to form heart shape. Repeat to make seven hearts. Cover and let rise 30 minutes on wire rack set over large pan to which hot water has been added. Preheat oven to 375.