Recreating Tonka Bean Gu Cake
In the oven at about 340/350 F, bake high quality/real white chocolate chunks or chips or buttons until evenly but lightly golden brown, moving it around with a wooden spoon or spatula. By doing this, you are caramelizing the sugars in the white chocolate = your caramel component. 

Remove from the oven and place into a container. Heat 35% whipping cream to a simmer and just cover the caramelized white chocolate. Less cream will make a thicker emulsion (more ganache style) and more cream will make a thinner emulsion (spreadable). While hot, add some sea salt or salt of choice. With a hand blender, whizz up the mixture until evenly combined and whipped. 

At this point you could use it as is (may need to heat slightly to use or spread), or you could opt to whip it further for a lighter, more mousse-style finish. 

This filling can be used in macarons, cake layers, thinned out as a sauce, a pudding, etc etc. I highly recommend this.