Make the caramel Add the peanut butter, maple syrup, vanilla extract and a pinch of salt to a bowl. Mix well until smooth and glossy. If the peanut butter is very thick, gently warm it (either sitting the jar in warm water or a few seconds in the microwave) to help it loosen. If you want the caramel runnier, add a little more maple syrup. For a thicker, fudgier caramel, mix in a bit more peanut butter. If needed, you can also add a teaspoon or two of coconut sugar to help create a more caramel-like texture.
Melt the chocolate: Break the dark chocolate into pieces and melt gently using a bain-marie or microwave in short bursts, stirring between each, until smooth.
Create the chocolate shells: Spoon or pour melted chocolate into the base of a silicone heart mould (or ice cube tray), just enough to coat the bottom evenly. Place in the fridge for about 10 minutes, or until just set.
Add the caramel centre: Once the chocolate base has set, add about ½ teaspoon of the peanut maple caramel into the centre of each heart.
Seal with chocolate: Spoon more melted chocolate over the caramel, filling the mould completely and smoothing the top if needed.
Set and enjoy: Return to the fridge for 20–30 minutes until fully set. Gently pop out of the mould and enjoy your gooey-centred Valentine Caramel Hearts