1. Place the butter or coconut oil in a 2-quart Pyrex bowl and microwave for 45 seconds.
2. Whisk the sugars, flour and salt into the butter to combine.
3. Whisk the coconut milk into the mixture until thoroughly blended. Add the eggs and combine.
4. Add the pumpkin puree and the mashed yams and whisk until a smooth batter is formed.
5. Combine the water with the spices in a small glass cup and microwave for 3 ½ minutes. Let the spices steep for 5 minutes. Strain the spiced water through a fine mesh strainer into the pumpkin-potato mixture and stir to incorporate.
7. Butter a 2-quart casserole and pour the mixture into the prepared dish.
8. Bake covered in a pre-heated 350°F oven for 1 hour. Serve hot out of the oven or reheated warm or hot.
Sugar pie pumpkins are about 1 ½ pounds and very rounded. Always use them when a recipe calls for cooked pumpkin. Larger pumpkins are more watery.
Coconut milk is not milk or dairy. It is the liquid formed from ground, fresh, hydrated coconut.