I spent many of my formative years in Florida, where Key limes are abundant. They are smaller and sweeter than the common limes sold in most markets. If you can’t find them (but try to— they’re very special!), a regular lime will do. This recipe also calls for agar agar, a natural gelatin derived from algae. It can usually be purchased where baking and cooking supplies are sold and, of course, can always be found online.
To make the crumble: Place the cashews, coconut flakes, coconut nectar, vanilla extract, and Key lime juice in a food processor and process until the mixture sticks together. Set aside and make the filling.
To make the coconut filling: Whisk the coconut cream, coconut nectar, vanilla extract, and Key lime zest together in a medium bowl. Pour into the parchment-lined pan and spread evenly with an offset spatula. Make the Key lime gelatin.
To make the Key lime gelatin: In a small bowl, combine the agar agar with the boiling water. Stir until dissolved. Add the matcha powder, coconut oil, Key lime juice, and honey, stirring until well combined. Allow to thicken for a few minutes before assembling the cheesecake.
To assemble the cheesecake: Sprinkle the crumble pieces and gelatin mixture on top of the coconut filling in the pan. Some gelatin will remain on the surface while other parts will sink, creating a beautiful bar once cut. Place the pan in the freezer until the dessert is fully frozen, about 4–6 hours. Cut into six 6x1" bars and serve immediately or store in the freezer.