Preheat oven to 350 degrees F. Grease a 9-inch glass pie plate with coconut oil.
In a large bowl, using a hand whisk, lightly whisk the eggs. Add the pumpkin, stevia, pumpkin pie spice and vanilla, and whisk until well incorporated.
Shake the coconut milk can well. Open the can, and stir it thoroughly. Now measure 1 cup (making sure again it's smooth and free of lumps) and add it to the pumpkin mixture, whisking to combine. Then whisk in the coconut flour.
Using a rubber spatula, transfer the mixture to the prepared pie plate. Bake until the center appears set (with just the slightest jiggle) and a toothpick inserted in it comes out just a little moist, but free of batter. In my oven, this takes about 40-45 minutes.
Cool the pie 2 hours on a cooling rack, then cover with plastic wrap and refrigerate for at least 2 hours before slicing and serving.
When ready to slice the keto crustless pumpkin pie, gently run a knife along the edges of the pie to help release it from the pan. Use a sharp knife to slice the pie, and firmly slide a cake server underneath each slice before you lift it up. The pie is fragile, so take care when you slice it and especially when you lift the slices up from the pan.