To make the devil's food cake:
To make the cream:
Whip the heavy cream until soft peaks, add the raspberry preserves and continue whipping until stiff peaks. Fill a pastry bag, fitted with a round pastry tip and pipe the cream on half of the heart shaped cakes.
To make the ganache:
Heat the strained apricot preserves in a saucepan over medium-low heat until melted. Add the cream, milk and corn syrup and heat just to simmer. Remove from the heat. Add all the chopped chocolate, swirl the pot to make sure the chocolate is completely covered by the cream. Let sit for about 3 minutes and then gently whisk until smooth.
With a small spatula, spread the refrigerated ganache over the sides of the cakes. The goal is to fill the gap between the layers of cake and make them smooth. We want a smooth surface so that when you pour the ganache over the cakes you will not have any bumps.
To pour the ganache on the cakes:
Slowly pour the ganache over the cake, starting in the middle and working outward. Be sure to check all the sides as you go. There will be a lot pooled up on the parchment, but you can scrape that up and melt to use again.
To make the blackberry coulis: