I used one piece of Therm O Web HeatnBond UltraHold in between two fabric hearts. You can't sew through this stuff so I didn't! I made a template that had tabs on top of the heart so I could sew the binding to. The tabs did not have HeatnBond so as to allow me to sew through them.
Really close up you can see I used a pink heart print for the binding and some white ric rac for trim. It was a quick project for a cute little girl.!