Heart fill swiss roll？
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It looks like a mousse filling or an ice cream to me. The heart was probably made first and frozen to hold its shape.
Get a heart shaped cookie cutter, make your filling, squeeze it into a log shape that is bigger than your cookie cutter, freeze it. When it is really frozen, take your cooke cutter and run the log through the cutter. I'm guessing they probably put the heart log in a cylinder then filled around it with the other two fillings. That's the only way I can think they got it so perfect.
The only reason I think the heart is made from ice cream and not cake is looking at the texture. If you look at the texture of the pink heart and chocolate heart, then look at the texture of the white stuff around it, you can see where the chocolate one sort of blended with the white. I would think the only thing that would still hold a heart shape when cut would be ice cream. Cake would hold that shape, but I just don't see that it's cake. It's too smooth. Not many air bubbles.
You can still use the canapé pans to achieve the heart too instead of a cookie cutter, but you will have to really push the ice cream out of it once frozen. Probably just set it in a pan of hot water very briefly to get it out. You can still use a cookie cutter to achieve that look if you don't want to buy another pan that you won't use very often. I had some from Pampered Chef and gave them to the Goodwill. haha.