Start by soaking your cashew nuts in plenty of water the night before.
Line an 18x27cm or similar sized pan (approximately 7x10.5 inches) with baking paper. This will make it easier to lift the whole cheesecake out later, to put on a board to slice.
To make the base, blitz pumpkin and sunflower seeds together in a food processor until they're a coarse powder. Add the dates, cocoa, salt and coconut oil, then blitz again until well combined. Press into the lined pan then refrigerate or freeze while you make the filling and topping.
Next, make your coconut caramel sauce. Put all of the sauce ingredients into a small saucepan and bring to a simmer. Continue to cook over a low heat, stirring often, for about 20 minutes or until the sauce is thick, glossy, and forms a channel through the sauce when you draw a spoon across the bottom of the pan.
While the sauce is cooking, make your popcorn. Heat 1 tablespoon coconut oil in a large saucepan with a lid. Once the oil is hot, add the popping corn and put the lid on. Let the corn pop, shaking the pan every now and then, until the sound of popping corn dies down again. Tip the popped corn out into a large mixing bowl.
Drain and rinse the cashews, then put into a high speed blender or food processor. Add the remaining cheesecake filling ingredients and blend until smooth, stopping to scrape down the sides a few times if needed.
Pour the cheesecake filling onto the cheesecake base and spread out evenly with a spatula.
Once the caramel sauce is done, pour about three quarters of it over the popcorn and stir to coat it evenly. Use your hands to break up the popcorn clumps a bit and arrange it evenly over the surface of the cheesecake, gently pushing it down into the cheesecake filling a little.
Drizzle the remaining caramel sauce over the surface of the cheesecake (reheat it if it's set), then freeze for at least six hours or until firm.
The cheesecake will slice more cleanly if cut while frozen (use your biggest, heaviest knife) and can then be stored in the freezer in portions. Allow to soften at room temperature for a little while before serving.
Notes
Prep time does not include soaking or chilling time.
Nutrition information is based on 12 generous bar sized portions, but you could easily cut those in half for 24 serves - which are still a lovely little treat.