Line two muffin pans with silicone or cupcake liners. This recipe makes 18 in a standard sized muffin pan.
Place crust ingredients into a bowl and stir until combined well. Press about 1.5 -2 tsp of crust into each cupcake liner then refrigerate.
Bloom gelatin by pouring cold water into a glass bowl. Sprinkle gelatin over water and let it stand for 5 minutes, do not stir. Warm in the microwave for 30 seconds then stir until dissolved. Set aside.
Beat cream cheese, sweetener, salt and vanilla in a stand mixer or large bowl with electric hand mixer until smooth. Pour cooled gelatin into mixer and until combined.
Pour heavy cream into the cream cheese mixture and blend on low until absorbed then increase speed for a couple minutes until it thickens and is well combined. Separate about 1/3 of this filling in a separate bowl to add on top of the pumpkin layer later.
Fold pumpkin puree and pumpkin spice into the remaining cream cheese mixture. Taste and adjust sweetener if needed.
Divide the pumpkin cheesecake filling into the cups. Spoon the reserved vanilla cheesecake on top of the pumpkin filling. Sprinkle pumpkin spice on top if desired then refrigerate at least 6 hours before serving.
Store covered in an airtight container in the fridge for up to 7 days.