Preheat your oven to 400°F / 200°C. Generously grease a 9-inch pie dish with 2 tablespoons (30 ml / 1 fl oz) of the butter.
Sprinkle the unsweetened coconut flakes evenly across the bottom of the dish.
Place the cubed pumpkin in a saucepan with a splash of water and a pinch of salt.
Bring to a boil over medium heat, then reduce heat, cover, and simmer for about 20 minutes, or until the pumpkin is fork-tender.
Drain any excess water.
Transfer the cooked pumpkin to a blender or use a hand blender.
Add the remaining 2 tablespoons (30 ml / 1 fl oz) of butter, keto sweetener, pumpkin pie spice, baking powder, salt, and heavy cream.
Blend until completely smooth and pureed.
In a separate bowl, use a hand mixer to whisk the eggs on high speed for 2-3 minutes until they are light, pale, and frothy.
Gently fold the smooth pumpkin mixture into the whisked eggs until just combined. Be careful not to overmix and deflate the eggs.
Pour the final mixture carefully over the coconut base in your prepared baking dish.
Bake for 20 minutes, or until the center is just set (it should have a slight jiggle).
Let it cool completely before serving.
